James Allan, Texas School for the Blind and VisuallyImpaired
Greg Lowney, Lowney Access Research
Kim Patch, Redstart Systems
Jeanne Spellman, W3C/Web Accessibility Initiative
UAAG 2.0 guidesdevelopers in designing user agents that make the webmore accessible to people with disabilities. User agents include browsers,browser extensions, media players, readers and other applications that render web content. A user agent that follows UAAG 2.0will improve accessibility through its own user interface and its ability tocommunicate with other technologies, including assistive technologies. UAAG and supportingresources are also intended to meet the needs of different audiences, includingdevelopers, policy makers, and managers. All users, not just users withdisabilities, will benefit from user agents that follow UAAG 2.0.
In addition tohelping developers of browsers and media players, UAAG 2.0 benefits developersof assistive technologies because it explains what types of information andcontrol an assistive technology can expect from a user agent that follows UAAG2.0. Assistive technologies not addressed directly by UAAG 2.0 (e.g. braillerendering) are still essential to ensuring web access for some users withdisabilities.
The "User AgentAccessibility Guidelines 2.0" (UAAG 2.0) is part of a series ofaccessibility guidelines published by the W3C Web Accessibility Initiative (WAI). UAAG isintroduced in the User Agent Accessibility Guidelines (UAAG) Overview.
This section describes the status ofthis document at the time of its publication. Other documents may supersedethis document. A list of current W3C publications and the latestrevision of this technical report can be found in the W3C technical reports index at http://www.w3.org/TR/.
W3C Working Group Note of UAAG 2.0
This is a W3C WorkingGroup Note of 15 December 2015 from the User Agent Accessibility Guidelines Working Group (UAWG). This Notewas Recommendation track work that closed before entering the CandidateRecommendation (CR) phase. Contributing factors included insufficient resourcesfor formal CR testing. A partial test suite is available, and at least twocandidate implementations have been identified for 90% of the features, but notformally tested.
- UAAG 2.0 completed Last Call in 2013 and UAWG has published 2 subsequent working drafts in response to comments.
- UAAG 2.0 has received wide review with 246 issues raised from 37 organizations or individuals representing browsers, media players, W3C working groups, and accessibility experts.
- All comments and issues have been resolved and there are no outstanding objections to UAAG 2.0.
- There are 3 features at risk where no implementations have been identified
- 1.4.5 Default to Platform Text Settings (examples of high contrast, but not text settings)
- 2.2.4 Options for Wrapping in Navigation
- 3.1.6 Form Submission Confirm
UAAG 2.0 addressesbarriers for people with disabilities that could be improved or solved withgreater user agent accessibility. UAWG hopes that publication of this Note willprovide user agent developers, people with disabilities, accessibility experts,and other involved parties a useful reference for improving the accessibilityof user agents.
Important changes tothis document since the previous version are highlighted below. A diff document of all changes is available.
- Changed term "Content Specifications" in 5.1.2 Implement Accessibility Features of Content Specifications to "Web Content Technology Specifications"
Comments on the Noteshould be sent to email@example.com (Public Archive). Although the UAWGis closing and will not respond to comments, comments can provide useful inputfor future work in this area.
Publication as aWorking Group Note does not imply endorsement by the W3C Membership. This is adraft document and may be updated, replaced or obsoleted by other documents atany time. It is inappropriate to cite this document as other than work inprogress.
This document wasproduced by a group operating under the 5 February 2004 W3C Patent Policy. W3C maintains a public list of any patentdisclosures made in connection with the deliverables of thegroup; that page also includes instructions for disclosing a patent. Anindividual who has actual knowledge of a patent which the individual believescontains Essential Claim(s) must disclose theinformation in accordance with section 6 of the W3C Patent Policy.
This document isgoverned by the 1 September 2015 W3C Process Document.
- Status of this Document
- UAAG 2.0 Layers of Guidance
- UAAG 2.0 Supporting Documents
- Components of Web Accessibility
- Levels of Conformance
- Relationship with Web Content Accessibility Guidelines(WCAG) 2.0
- Relationship with Authoring Tool Accessibility Guidelines (ATAG) 2.0
- UAAG 2.0 Guidelines
- UAAG 2.0 Conformance Applicability Notes
- PRINCIPLE 1: Perceivable
- Guideline 1.1: Alternative content
- Guideline 1.2: Missing content
- Guideline 1.3: Highlighting
- Guideline 1.4: Text configuration
- Guideline 1.5: Volume configuration
- Guideline 1.6: Synthesized speech configuration
- Guideline 1.7: User style sheet configuration
- Guideline 1.8: Orientation in viewports
- Guideline 1.9: Alternative views
- Guideline 1.10: Element Information
- PRINCIPLE 2: Operable
- Guideline 2.1: Keyboard access
- Guideline 2.2: Sequential navigation
- Guideline 2.3: Direct navigation and activation
- Guideline 2.4: Text Search
- Guideline 2.5: Structural navigation
- Guideline 2.6: Preference settings
- Guideline 2.7: Graphical controls
- Guideline 2.8: Time-independent interaction
- Guideline 2.9: Flashing
- Guideline 2.10: Time-based media
- Guideline 2.11: Other Input Devices
- PRINCIPLE 3: Understandable
- PRINCIPLE 4: Programmatic access
- PRINCIPLE 5: Specifications and conventions
- Appendix A: Glossary
- Appendix B: How to refer to UAAG 2.0 from other documents
- Appendix C: References
- Appendix D: Acknowledgements
This document isdivided into two types of sections. The normative sections are:principles, guidelines, success criteria, notes, conformance, and glossary.These are required to claim conformance to UAAG 2.0. The other sections of thisdocument, including this introduction, Appendix B, C and D, are informative. They explain andamplify the normative sections.
A user agent is anysoftware that retrieves, renders and facilitates end-user interaction with webcontent. User agents include web browsers, media players, add-ons (plug-ins &extensions), and web applications that help in retrieving, rendering andinteracting with web content. UAAG 2.0 specifies requirements for user agent developers that willlower barriers to accessibility.
For an introductionto UAAG, see the User Agent Accessibility Guidelines (UAAG) Overview.
Improvingaccessibility means considering a wide range of disabilities. These includevisual, auditory, physical, speech, cognitive, language, learning, neurologicaldisabilities, and disabilities related to aging. The goal of UAAG 2.0 is toensure that all users, including users with disabilities, have equal controlover the environment they use to access the web.
Some users have morethan one disability, and the needs of different disabilities can conflict. ManyUAAG 2.0 requirements use configuration preferences to ensure that a featuredesigned to improve accessibility for one user does not interfere with theneeds of another user. To avoid overwhelming users with an abundance ofconfiguration options, UAAG 2.0 includes requirements that promote clear documentationand ease of configuration.
The UAWG expects thatsoftware that satisfies the requirements of UAAG 2.0 will be more flexible,manageable, extensible, and beneficial for a broad range of users.
UAAG 2.0 Layers of Guidance
In order to meet theneeds of different audiences, UAAG provides three layers of guidance: overall principles,general guidelines, and testable success criteria. There is moredetail for each success criterion in a separate document, UAAG 2.0 Reference, includingexplanatory intent, examples of how the criterion can apply in different usersituations, and links to resources.
- Principles – Five principles provide a foundation for accessible user agents. Principles 1, 2, and 3 are parallel to Web Content Accessibility Guidelines (WCAG) 2.0. Principles 4 and 5 are specific to user agents.
- Principle 1 ensures that the user agent is perceivable, so users can access user agent output
- Principle 2 ensures that the user agent is operable, so users can communicate with the user agent
- Principle 3 ensures that the user agent is understandable, so users know what to do to use the user agent
- Principle 4 ensures that assistive technologies can access user agent controls
- Principle 5 ensures that user agents comply with other accessibility specifications (e.g WCAG) and platform conventions (e.g. Windows, iOS, Linux, Blackberry).
Each success criterion is assigned a level. The levels are designed to meet the needs of different groups and different situations: A (minimum conformance), AA (recommended conformance), and AAA ( advanced conformance). Additional information on UAAG levels can be found in the Levels of Conformance section.
UAAG 2.0 Supporting Documents
A separate document,entitled UAAG 2.0 Reference: Explanations, Examples, and Resources for User AgentAccessibility Guidelines 2.0 (hereafter referred to as the"Reference document") provides explanations and examples of how eachsuccess criteria might be satisfied. It also includes references to otheraccessibility resources (such as platform-specific software accessibilityguidelines) that provide additional information on how a user agent can satisfyeach success criteria. The examples in UAAG 2.0 Reference are informative only. Other strategiescan be used or required to satisfy the success criteria. The UAWG expects toupdate UAAG 2.0 Reference more frequently than the User Agent AccessibilityGuidelines 2.0. Developers, W3C Working Groups, users, and othersare encouraged to contribute examples and resources to UAAG 2.0 Reference.
Web accessibilitydepends on both accessible user agents and accessible content. The level ofaccessibility of content is largely influenced by the authoring tool used tocreate it. For an overview of how these components of web development andinteraction work together, see
- Essential Components of Web Accessibility
- Web Content Accessibility Guidelines (WCAG) Overview
- Authoring Tool Accessibility Guidelines (ATAG) Overview
User agents canconform to UAAG 2.0 at one of three conformance levels: levels A (minimum), AA(recommended), and AAA (advanced). The three levels of UAAG 2.0 conformance arebased on the corresponding level designations (A, AA, or AAA) of the individualsuccess criteria (i.e., specific requirements). The user agent can conform to alevel by meeting the success criteria of that level and the levels below it.
- Level A conformance: The user agent complies with all applicable level A success criteria.
- Level AA conformance: The user agent complies with all applicable level A and AA success criteria
- Level AAA conformance: The user agent complies with all applicable level A, AA, and AAA success criteria.
UAAG 2.0 has manyoptions that can be managed through preference settings.
For details aboutwhat each level represents, how the levels were determined, and how user agentdevelopers and managers can use the levels for prioritizing accessibilityimprovements and designing user interfaces, see UAAG 2.0 Reference Levels ofConformance .
The W3Crecommendation, Web Content Accessibility Guidelines (WCAG), applies to all webcontent; UAAG provides additional advice on the application user interface.
Some user agents areused to package web content into native applications, especially on mobileplatforms. If the finished application is used to retrieve, render, andfacilitate end-user interaction with web content of the end-users choosing,then the application should be considered a stand-alone user agent. If thefinished application only renders a constrained set of content specified by thedeveloper, then the application might not be considered a user agent. In bothcases, the WCAG 2.0 Guidelines apply to the web content. If the application isnot a user agent, application developers are not responsible for UAAG 2.0requirements that extend beyond WCAG 2.0 requirements. For more detail, see thedefinition of user agent.
While it is common tothink of user agents retrieving and rendering web content for one group ofpeople (end-users) that was previously authored by another group (authors),user agents are also frequently involved with the process of authoring content.
For these cases, itis important for user agent developers to consider the application of anotherW3C-WAI Recommendation, the Authoring Tool Accessibility Guidelines (ATAG). ATAG (currently 2.0is in draft) provides guidance to the developers of tools regarding theaccessibility of authoring interfaces to authors (ATAG 2.0 Part A) and ways inwhich all authors can be supported in producing accessible web content (ATAG2.0 Part B).
For more informationon the role of user agents in web authoring see UAAG 2.0 Reference
The ConformanceApplicability Notes are a list of normative conditions that apply broadly tomany of the success criteria in these guidelines. Generally, the notes clarifyhow the success criteria would apply under certain circumstances.
- Retrieved Content Only: UAAG 2.0 success criteria only apply to web content that has been retrieved by the user agent (e.g. if a user agent saves bandwidth by retrieving video element content only on demand, then captions associated with that video content do not need to be searchable as per 2.4.5 until the video is retrieved).
- Current Content Only: At any point in time, UAAG 2.0 success criteria only apply to web content that has not been hidden or removed (e.g., a bookmark created as per 1.8.16 will no longer be operable if the content it refers to is hidden or removed).
- Recognized Content Only: UAAG 2.0 success criteria only apply to web content and its behaviors that can be recognized by user agents.
- Optional Settings: Throughout UAAG 2.0, all required behaviors can be provided as optional preference settings unless a success criterion explicitly says otherwise. For example, if a success criterion requires high contrast between foreground text and its background, the user agent can also provide choices with low contrast. While it is preferred to have a required behavior as a default option, it does not need to be, unless the success criterion explicitly says otherwise.
- RFC 2119 language not used: UAAG 2.0 does not use RFC 2119 language (must, may, should) as it is not an interoperable specifications. Note, even if these terms appear from time to time they do not have any RFC 2119 implication.
- Simultaneous satisfaction of success criteria: Users can access all behaviors required by UAAG 2.0 at the same time (e.g. when the user resizes the viewport per 1.8.8, content is reflowed per 1.8.6), except where those behaviors are mutually exclusive.
- Vertical layout languages: When user agents render vertical layout languages (e.g. Mongolian, Han), success criteria normally relating to horizontal rendering should be applied to vertical rendering instead.
- Add-ons (Extensions and Plug-ins): Success criteria can be met by a user agent alone or in conjunction with add-ons, as long as those are:
- discoverable by the user
- no extra cost to the user
- easily installed (i.e. not requiring expert knowledge or editing of configuration files, databases, or registry entries)
- Relationship with operating system or platform: The user agent does not need to implement every behavior itself. A required behavior can be provided by the platform, user agent, user agent add-ons, or potentially other layers. All are acceptable, as long as they are enumerated in the conformance claim.
- Platform limitations: If the platform (hardware or operating system) does not support a capability necessary for a given UAAG 2.0 success criterion, see Components of UAAG 2.0 Conformance Claims #8.
- Override author settings for text configuration: All of the success criteria under guideline 1.4 allow users to override the text characteristics specified by authors, and override user agent defaults.
Guideline 1.1 -Provide access to alternative content [Reference for 1.1]
Note: It is recommended that the user agent allow the user to choose whetherthe alternative content replaces or supplements the original content element.
The user can requesta placeholder that incorporates recognized text alternativecontent instead of recognized non-text content, until explicit user request torender the non-text content. (Level A)
For recognized on-screenalternative content for time-based media (e.g. captions, sign language video),the following are all true: (Level A)
Don't obscure controls: Displayingtime-based media alternatives doesn't obscure recognized controlsfor the primary time-based media.
Don't obscure primary media: The user can specifythat displaying time-based media alternatives doesn't obscure the primarytime-based media.
Note: Depending on the screen areaavailable, the display of the primary time-based media can need to be reducedin size to meet this requirement.
The user can specifywhich type(s) of alternative content to render by default for each typeof non-text content, including time based media. (Level AA)
For recognized on-screenalternative content for time-based media (e.g. captions, sign language video),the user can configure recognized text within time-based media alternatives(e.g. captions) in conformance with 1.4.1. (Level AA)
The user canconfigure recognized alternative contentfor time-based media (e.g. captions, sign language video) as follows: (Level AAA)
Resize: The user can resizealternative content for time-based media to at least 50% of the size of the top-level viewports.
Reposition: The user canreposition alternative content for time-based media to two or more of thefollowing: above, below, to the right, to the left, and overlapping the primarytime-based media.
Note 1: Depending on the screen areaavailable, the display of the primary time-based media can need to be reducedin size or hidden to meet this requirement.
Note 2: Implementation can involvedisplaying alternative content for time-based media in a separate viewport, butthis is not required.
Guideline 1.2 - Repair missingcontent [Reference for 1.2]
If text alternativesfor non-text content are missing or empty, the user agent doesn't attempt torepair the text alternatives by substituting text values that are alsoavailable to assistive technologies (e.g. image file name). (Level AA)
Guideline 1.3 -Provide highlighting for selection, keyboard focus, enabled elements, visitedlinks [Reference for 1.3]
The user can have thefollowing types of content uniquely highlighted, overriding any valuesspecified by the author: (Level A)
In-page search results
Active keyboard focus (indicated by focus cursors and/ortext cursors)
The user can set allof the following characteristics of selection highlighting, overriding anyvalues specified by the author: (Level AA)
The user can set allof the following characteristics of active keyboard focus highlighting,overriding any values specified by the author: (Level AA)
Border (color, style, and thickness)
Text cursor blink rate
The user can set allof the following characteristics of enabled element highlighting, overridingany values specified by the author: (Level AA)
Border (color, style, and thickness)
The user can set allof the following characteristics for visited links and separately for unvisitedlinks, overriding any values specified by the author: (Level AA)
Guideline 1.4 - Provide textconfiguration [Reference for 1.4]
Note 1: The successcriteria in guideline 1.4 can be met through user stylesheets. For platformswithout user stylesheets, text configuration needs to be provided to usersthrough the user agent's main user interface or via an add-on.
Note 2: Users have varyingneeds for text size and spacing. Therefore, it’s recommended that user agentsprovide a wider range of values, and a greater number of increments, to allowthe user to adjust the view for their current task.
Text scale with preserved sizedistinctions (e.g. keeping headings proportional to main font)
Text color and background color,choosing from all platform color options
Font family, choosing from allinstalled fonts
Line spacing, choosing from a rangewith at least three values up to at least 2 times the default
Text style, choosing to turn on/offunderline, italic, bold
The user can set allof the following characteristics of visually rendered text content for textelement types including at least headings, input fields, and links: (Level AA)
Text size (e.g. 18 point) or scale(e.g. 150%)
Text color and background color,choosing from all platform color options
Font family, choosing from at leastall installed fonts
Line spacing, choosing from a rangewith at least three values up to at least 2 times the default
Text style, choosing to turn on/offunderline, italic, bold
Margins around blocks of text
Character spacing, choosing from arange with at least 5 values
Justification (left or right,including turning off full justification)
Margins around blocks of text
The user can printthe rendered content, and the following are all true: (Level AA)
any visual, non-time-based, renderedcontent can be printed
the user can choose between available printing devices
the user can have content printed asit is rendered on screen, reflecting any user scaling, highlighting, and othermodifications
the user can have printed contentreflow as if the top-level viewports had been resized to match thehorizontal dimension of the printing device's printable area
The user can specifythat platform text settings be used as the default values for textconfiguration. (Level AA)
Capitalization (overriding uppercase and small caps style)
Word-breaking properties (e.g.auto-hyphenation)
Word spacing (choosing from a rangeof at least 5 values)
Note: This successcriterion does not apply to text entered as all caps. Content authors areencouraged to use styles instead of typing text as all caps.
Guideline 1.5 -Provide volume configuration [Reference for 1.5]
Guideline 1.6 -Provide synthesized speech configuration [Reference for 1.6]
Note: If browsers providespeech output for mainstream users, they should make the speech configurableenough to be usable by a wide range of individuals. When an add-on adds speechoutput to the user agent, it becomes part of the user agent, and thereforeshould meet the requirements of 1.6.
If synthesized speechis produced, the user can specify the following: (Level A)
Speech volume (independently ofother sources of audio)
Voice, when more than one voice isavailable
If synthesized speechis produced, the user can specify the following if offered by the speechsynthesizer: (Level AA)
Pitch (average frequency of thespeaking voice)
Pitch range (variation in averagefrequency)
Note: Because the technicalimplementations of text to speech engines vary (e.g. formant-based synthesis,concatenative synthesis), a specific engine may not support varying pitch orpitch range. A user agent should expose the availability of pitch and pitchrange control if the currently selected or installed text to speech engineoffers this capability.
If synthesized speechis produced, the following features are provided: (Level AA)
User-defined add-ons to the synthesizedspeech dictionary.
"Spell-out": text is spelled onecharacter at a time, or according to language-dependent pronunciation rules.
At least two ways of speakingnumerals: spoken as individual digits and punctuation (e.g. "one two zero threepoint five" for 1203.5 or "one comma two zero three point five"for 1,203.5), and spoken as full numbers are spoken (e.g. "one thousand,two hundred and three point five" for 1203.5).
At least two ways of speakingpunctuation: spoken literally, and with punctuation understood from speechcharacteristics like pauses.
If synthesized speechis produced and more than one language is available, the user can change thelanguage. (Level AA)
If synthesized speechis produced, the user can adjust all of the speech characteristics provided bythe speech synthesizer. (Level AAA)
Guideline 1.7 -Enable configuration of user stylesheets [Reference for 1.7]
If the user agentsupports a mechanism for author styles, the user can disable the use ofauthor styles on the current page. (Level A)
If the user agentsupports a mechanism for author styles, the user agent also provides amechanism for a user styling to override author styling. (Level A)
If user styles are supported, then the user canenable or disable user styles for: (Level A)
All pages on specified websites, or
The user can savecopies of the stylesheets referenced by the current page. This allows the userto edit and load the copies as user stylesheets. (Level AA)
Guideline 1.8 -Help users to orient within, and control, windows and viewports [Reference for 1.8]
The user can have theviewport with the input focusbe highlighted. (Level A)
When a viewport's selection or input focus changes, the viewport's content moves asnecessary to ensure that the new selection or input focus location is at leastpartially in the visible portion of the viewport. (Level A)
The user can rescalecontent within top-level graphical viewports as follows: (Level A)
Zoom in: to 500% or more ofthe default size
Zoom out: to 10% or less ofthe default size, so the content fits within the height or width of theviewport
Note: When the point of regard is largerthan the viewport, the user agent keeps visible the beginning of the point ofregard according to the current language's reading order (e.g. top-left inEnglish)
For user agents that implement a history mechanismfor top-level viewports (e.g. "back" button), theuser can return to any state in the viewport history that is allowed by thecontent, including: (Level AA)
restored point of regard
input focus, and
user's form field entries
Note: It is recommended that selectionalso be restored.
The user can specifywhether author content can open new top-level viewports (e.g. windows or tabs). (Level AA)
If new top-level viewports (e.g. windows or tabs) areconfigured to open without explicit user request, the user can specify whetheror not top-level viewports take the active keyboard focus when they open. (Level AA)
The user can specifythat all top-levelviewports (e.g. windows or tabs) follow the defined userinterface configuration. (Level AA)
The user can specifythat recognized multi-column text blocks each be reflowed into a single column.(Level AA)
Note: Some layouts may become unusable ifauthor-specified layout is overridden. In this case, the user can turnlinearization off and try another strategy. It is recommended that user agentsprovide a convenient way for the user to turn this behavior on and off.
The user can have theuser agent override author-specified unit dimensions. (Level AA)
The user can haverecognized content rendered as a single column, overriding author-specifiedformatting of columns, tables, and positioning. (Level AA)
Note: Some layoutsmay become unusable if author-specified layout is overridden. In this case, theuser can turn linearization off and try another strategy. It is recommendedthat user agents provide a convenient way for the user to turn this behavior onand off.
The user can markitems in a web page, then use shortcuts to navigate back to marked items. Theuser can specify whether a navigation mark disappears after a session, or ispersistent across sessions. (Level AAA)
Guideline 1.9 -Provide alternative views [Reference for 1.9]
Note: Note: An outline view might alsoinclude other named elements such as document landmarks.
Guideline 1.10 - Provide elementinformation [Reference for 1.10]
The user can accessthe information from explicitly-defined relationships in the content, includingat least the following: (Level AA)
calculated accessible name forimages
calculated accessible name forcontrols (e.g. form fields, buttons)
caption for a table
row and column labels for a tablecell
The user candetermine the path of element nodes going from the root element of the elementhierarchy to the currently focused or selected element. (Level AAA)
- Note: Modality Independence: Users interacting with a web browser may do so using one or more input methods including keyboard, mouse, speech, touch, and gesture. It's critical that each user be free to use whatever input method, or combination of methods, works best for a given situation. If every potential user task is made accessible — so multiple modalities are supported — a user can choose what works best. For instance, if a user can't use or doesn't have access to a mouse, but can use and access a keyboard, the keyboard can call a modality independent control to activate an OnMouseOver event. Another example is a user on a mobile device that lacks keyboard who uses uses taps, wirelessly connected devices, and voice commands to simulate discrete or keyboard input. See Independent User Interface: Events for additional information on APIs and techniques for modality independent controls.
Guideline 2.1 -Ensure full keyboard access [Reference for 2.1]
All functionality canbe operated via the keyboard using sequential or direct keyboardcommands that do not require specific timings for individual keystrokes, exceptwhere the underlying function requires input that depends on the path of theuser's movement and not just the endpoints (e.g. free hand drawing). This doesnot forbid and should not discourage providing other input methods in additionto keyboard operation including mouse, touch, gesture and speech. (Level A)
If keyboard focus can be moved to a component using akeyboard interface (including nested user agents), then focus can be moved awayfrom that component using only a keyboard interface. If this requires more thanunmodified arrow or Tab keys (or standard exit methods like Escape), users areadvised of the method for moving focus away. (Level A)
The user can specifythat focus and selection can be moved without the user agent or author-suppliedcontent further changing focus, selection, or the state of controls. (Level A)
The user agentfollows keyboard conventions for the operating environment. (Level A)
The user agent user interface includes mechanismsto make keyboard access more efficient than sequential keyboard access. (Level A)
Guideline 2.2 -Provide sequential navigation [Reference for 2.2]
The user can move thekeyboard focus backwards and forwards between regions identified by documentlandmarks. (Level A)
Note: The user agent might also includeother regions, such as viewports, in the sequential navigation.
If the author has notspecified a navigation order, the user can have the default sequentialnavigation order be the source order. (Level AA)
The user can requestnotification when sequential navigation wraps at the beginning or end of adocument, and can prevent such wrapping. (Level AA)
Guideline 2.3 -Provide direct navigation and activation [Reference for 2.3]
The user can have anydirect commands in the UA user interface (e.g. keyboard shortcuts) bepresented with their associated user interface controls (e.g."Ctrl+S" displayed on the "Save" menu item and toolbarbutton). (Level AA)
The user can remapany keyboard shortcut including recognized authorsupplied shortcuts (e.g. accesskeys) and UA user interface controls, except for conventionalbindings for the operating environment (e.g. arrow keys for navigatingwithin menus). (Level AA)
Guideline 2.4 - Provide text search[Reference for 2.4]
The user can performa search within rendered content, including rendered textalternatives and rendered generated content, for any sequence of printingcharacters from the document character set. (Level A)
The user can searchforward or backward in rendered content. (Level A)
When a searchoperation produces a match, the matched content is highlighted, the viewport is scrolled ifnecessary so that the matched content is within its visible area, and the usercan search from the location of the match. (Level A)
The user can chooseto receive notification when there is nomatch to a search operation. The user can choose to receive notification whenthe search continues from the beginning or end of content. (Level A)
The user can performtext searches within alternative content that is text (e.g. text alternatives for non-text content, captions) even whenthe alternative content is not rendered onscreen. (Level AA)
Guideline 2.5 -Provide structural navigation [Reference for 2.5]
The user agentprovides at least the following types of structural navigation, where the structure types arerecognized: (Level AA)
By content sections
Guideline 2.6 - Configure and storepreference settings [Reference for 2.6]
User agentaccessibility preference settings persist between sessions. (Level A)
Note: User agents may have a publicaccess setting that turns this off.
The user can restoreall preference settings to default values. (Level A)
The user can save andretrieve multiple sets of user agent preference settings. (Level AA)
The user can adjustany preference settings required to meet the User Agent AccessibilityGuidelines (UAAG) 2.0 from outside the UA user interface. (Level AAA)
The user can transferall compatible user agent preference settings between devices. (Level AAA)
Guideline 2.7 - Customizedisplay of graphical controls [Reference for 2.7]
The user cancustomize which user agent commands, functions, and add-ons are displayed withinthe user agent user interface as follows: (Level AA)
Show: The user can chooseto display any controls available within the user agent user interface,including user-installed add-ons. It is acceptable to limit the total number ofcontrols that are displayed onscreen.
Simplify: The user cansimplify the default user interface by choosing to display only commandsessential for basic operation (e.g. by hiding some controls).
Reposition: The user can chooseto reposition individual controls within containers (e.g. toolbars or toolpalettes), as well as reposition the containers themselves to facilitatephysical access (e.g. to minimize hand travel on touch screens, or tofacilitate preferred hand access on handheld mobile devices).
Assign Activation Keystrokes orGestures: The user can choose to view, assign or change default keystrokes orgestures used to activate controls.
Reset: The user has theoption to reset the containers and controls to their default configuration.
Guideline 2.8 -Allow time-independent interaction [Reference for 2.8]
The UA user interface does not include time limits or atleast one of the following is true: (Level A)
Turn Off: Users are allowed toturn off the time limit before encountering it; or
Adjust: Users are allowed toadjust the time limit before encountering it over a wide range that is at leastten times the length of the default setting; or
Extend: Users are warnedbefore time expires and given at least 20 seconds to extend the time limit witha simple action (e.g. "press the space bar"), and users are allowedto extend the time limit at least ten times; or
Real-time Exception: The time limit is arequired part of a real-time event and no alternative to the time limit ispossible; or
Essential Exception: The time limit isessential and extending it would invalidate the activity; or
20 Hour Exception: The time limit islonger than 20 hours.
Guideline 2.9 -Help users avoid flashing that could cause seizures [Reference for 2.9]
In its defaultconfiguration, the user agent does not display any UA user interface componentsthat flashes more than three times in any one-second period, unless the flashis below general flash and red flash thresholds. (Level A)
In its defaultconfiguration, the user agent does not display any UA user interface componentsthat flashes more than three times in any one-second period (regardless ofwhether not the flash is below the general flash and red flash thresholds). (Level AAA)
The user can adjustthe playback rate of prerecorded time-based media content, such that all of thefollowing are true: (Level AA)
Playback Rate: The user can adjustthe playback rate of the time-based media tracks to between 50% and 250% ofreal time.
Pitch: Speech whoseplayback rate has been adjusted by the user maintains pitch in order to limitdegradation of the speech quality.
Synchronization: Audio and videotracks remain synchronized across this required range ofplayback rates.
Reset: The user agentprovides a function that resets the playback rate to normal (100%).
The user can stop,pause, and resume rendered audio and animation content (e.g video, animation,changing text) that lasts three or more seconds at the default playback rate. (Level A)
If time-based medialasts three or more seconds at the default playback rate, the user can navigateit using a continuous scale and by relative time units. (Level A)
The user can navigateby semantic structure within the time-based media, such as by chapters orscenes present in the media. (Level AA)
Users can adjust thecontrast and brightness of visual time-based media. (Level AAA)
If an input device issupported by the platform, all user agent functionalityincluding text input can be operated using that device. (Level AA)
The user can reverse recognized text entry actionsprior to submission. (Level A)
Note: Submission can be triggered in manydifferent ways, such as clicking a submit button, typing a key in a controlwith an onkeypress event, or by a script responding to a timer.
If the user agentprovides mechanisms for changing its user interface settings, it either allowsthe user to reverse the setting changes, or the user agent can require userconfirmation to proceed. (Level A)
By default, the useragent shows the state of content retrieval activity. (Level A)
The user can havespelling assistance for editable text in rendered content. (Level AA)
The user can reverse recognized navigation betweenweb addresses (e.g. standard "back button" functionality). (Level AA)
The user can specifywhether or not recognized form submissionsmust be confirmed. (Level AA)
The user can have thefollowing information stored and used to auto-fill form fields by request: (Level AA)
user's email address
user's phone number
If the user agentprovides a feature to save local versions of web content, then any form fieldsthe user has filled retain any entries in the saved version. (Level AA)
Product documentation is available in a format that meetssuccess criteria of WCAG 2.0 level "A" or greater. (Level A)
For each user agentfeature that is used to meet UAAG 2.0, at least one of the following is true: (Level A)
Described in the Documentation: Use of the featureis explained in the user agent's documentation; or
Described in the Interface: Use of the featureis explained in the UA user interface; or
Platform Service: The feature is aservice provided by an underlying platform; or
Not Used by Users: The feature is notused directly by users (e.g., passing information to a platform accessibilityservice).
For each user agentfeature, at least one of the following is true: (Level AA)
Described in the Documentation: Use of the featureis explained in the user agent's documentation; or
Described in the Interface: Use of the featureis explained in the UA user interface; or
Platform Service: The feature is aservice provided by an underlying platform; or
Not Used by Users: The feature is notused directly by users (e.g., passing information to a platform accessibilityservice).
Changes to featuresthat meet UAAG 2.0 success criteria since the previous user agent release aredocumented. (Level AA)
There is a dedicatedsection of the documentation that presents a view of all features of the useragent necessary to meet the requirements of User Agent Accessibility Guidelines2.0. (Level AAA)
Guideline 3.3 -Make the user agent behave in predictable ways [Reference for 3.3]
The user can preventfocus changes that are not a result of explicit user request. (Level A)
Guideline 4.1 - Facilitateprogrammatic access to assistive technology [Reference for 4.1]
Note: UAAG 2.0 assumesthat a platform accessibility service will be built on top of underlyingsecurity architectures that will allow user agents to comply with both thesuccess criteria and security needs.
The user agentsupports relevant platform accessibility services. (Level A)
For all userinterface components (including UA user interface, rendered content, and generated content) the useragent makes available the followingproperties and any change notifications via a platform accessibility service: (Level A)
Name, Role, State
Bounding dimensions and coordinates
Font family of text
Foreground and background color fortext
Explicitly defined relationships(e.g. ARIA relationships [ARIA 1.0])
If UA user interface functionality cannot be exposedthrough platform accessibility services, then the user agentprovides equivalent functionality that can be exposed through the platformaccessibility service. (Level A)
If the user agentaccessibility API does not provide sufficient information to one or moreplatform accessibility services, then Document Object Models (DOM), must bemade programmatically available to assistive technologies. (Level A)
If the user caninteract with content (e.g. by checking a box or editing a text area), the samedegree of interaction is programmatically available. (Level A)
Guideline 5.1 -Comply with applicable specifications and conventions [Reference for 5.1]
Web-based UA user interfaces meet the WCAG 2.0 success criteria.(Level A to meet WCAG 2.0 Level A successcriteria; Level AA to meet WCAG 2.0 Level A and AA successcriteria; and Level AAA to meet WCAG 2.0 Level A, AA, and AAA successcriteria)
Note: This success criterion does notapply to native UA user interfaces, but does include any parts of native useragents that are web-based (e.g. help systems). However, it is recommended thatdevelopers of native user agent user interfaces follow the Guidance on ApplyingWCAG 2.0 to Non-Web Information and Communications Technologies (WCAG2ICT) [WCAG2ICT].
Implement theaccessibility features of web content technology specifications. Accessibilityfeatures are those that are either (Level A):
Identified as such in the contentspecifications or
Allow authors to satisfy arequirement of WCAG 2.0
Note 1: If a conformance claim is filed,cite the implemented specifications in the conformance claim. See Components of a UAAG 2.0 ConformanceClaim - #9 Web Content Technologies.
Note 2: When a rendering requirement ofanother specification contradicts a requirement of UAAG 2.0, the user agent candisregard the rendering requirement of the other specification and stillsatisfy this guideline.
If the user agentcontains native user interfaces, then those native user interfaces follow userinterface accessibility guidelines for the platform. (Level A)
The user can selectcontent elements and have them rendered in alternative viewers. (Level AA)
The user agentprovides a mechanism for users to report user agent accessibility issues. (Level AAA)
This section isnormative.
Conformance meansthat the user agent satisfies the success criteria defined in the guidelines section.This section lists requirements for conformance and conformance claims.
In order for a webpage to conform to UAAG 2.0, one of the following levels of conformance is metin full.
- Level A: For level A conformance (the minimum level of conformance), the user agent satisfies all the Level A success criteria.
- Level AA: For level AA conformance (recommended), the user agent satisfies all level A and level AA Success Criteria.
- Level AAA: For level AAA conformance (advanced), the user agent satisfies all level A, level AA and level AAA Success Criteria.
The Conformance Applicability Notes provide additionalguidance on the applicability of the success criteria under certaincircumstances.
Although conformancecan only be achieved at the stated levels, developers are encouraged to report(in their claim) any progress toward meeting success criteria from all levelsbeyond the achieved level of conformance.
If a conformanceclaim is made, the conformance claim must meet the following conditions:
- At least one version of the conformance claim must be published on the web as a document meeting level "A" of WCAG 2.0. A suggested metadata description for this document is "UAAG 2.0 Conformance Claim".
- Whenever the claimed conformance level is published (e.g. product information website), the URI for the on-line published version of the conformance claim must be included.
- The existence of a conformance claim does not imply that the W3C has reviewed the claim or assured its validity.
- There are no restrictions on who can make a claim.
- Claimants are solely responsible for the accuracy of their claims.
- Claimants are encouraged to claim conformance to the most recent version of the User Agent Accessibility Guidelines Recommendation.
- Claimant name and affiliation
- Claimant contact information
- Date of the claim
- Type of compliance: [ ] User Agent (full) [ ] Add-on only (limited)
- Conformance level satisfied
- User agent information:
- Name and manufacturer
- Version number or version range
- Required patches or updates, language of the user interface and documentation (e.g. English, French, Chinese)
- Plug-ins or add-ons (including version numbers) needed to meet the success criteria (e.g. mouseless browsing)
- Configuration changes to the user agent, plug-ins and add-ons that are needed to meet the success criteria (e.g. ignore author foreground/background color, turn on Carat Browsing)
- Platform: Provide relevant information about the software and/or hardware platform(s) that the user agent relies on for conformance. This information can include:
- Name and manufacturer
- Version of key software components (e.g. operating system, other software environment)
- Hardware requirements (e.g. audio output enabled, minimum screen size: 2", bluetooth keyboard attached)
- Operating system(s) (e.g. Windows, Android, iOS, GNOME)
- Other software environment (Java, Eclipse)
- Host web browser when the conforming user agent is web-based (e.g. JW Player on Firefox)
- Configuration changes to the platform that are needed to meet the success criteria (e.g. turn on Sticky Keys, use High Contrast Mode)
- Platform Limitations: If the platform (hardware or operating system) does not support a capability necessary for a given UAAG 2.0 success criterion, list the success criterion and the feature (e.g. a mobile operating system does not support platform accessibility services, therefore the user agent cannot meet success criterion 4.1.2). For these listed features, the user agent can claim that the success criteria do not apply (see 10.b.1 following).
- Declarations: For each success criterion, provide a declaration of either
- whether or not the success criterion has been satisfied; or
- declaration that the success criterion is not applicable and a rationale for why not, from the following choices:
- Platform: not applicable due constraints of the platform, per Paragraph 7 above (e.g. color handling on a monochrome device, video handling in a purely audio browser, or interprocess communication on an operating system that does not support multitasking). Describe the specific platform limitation.
- Input: not applicable due to a constrained input set (e.g. a help system that only displays the HTML files included with the product)
- Output: not applicable due to intentionally limited output modalities (e.g. video handling in a browser that only does audio output, even though the platform can support video)
This option can beused for a user agent add-on or plug-in with limited functionality that wishesto claim UAAG 2.0 conformance. An add-on or plug-in can claim conformance for aspecific success criterion or a narrow range of success criteria as stated inthe claim. All other success criteria can be denoted as Not Applicable.
UAAG recognizes thatsome add-ons can be so specialized to the needs of a particular disability thatthe add-on is mutually exclusive with other success criteria of UAAG, but thegoal would be for add-ons to work with the user agent so that any features ofthe user agent needed for UAAG conformance are not broken by one add-on. If theadd-on limits other accessibility features of the user agent, then include astatement to that effect, such as: "This add-on breaks success criterionx.x.x because it is intended to meet [foo] need of [this] class of user."An example would be a (hypothetical) add-on that breaks 1.8.2 and 1.8.3(viewport navigation) to provide a simplified page for people with highdistraction levels.
A description of howthe UAAG 2.0 success criteria were met where this is not obvious.
Neither W3C, WAI, norUAWG take any responsibility for any aspect or result of any UAAG 2.0conformance claim that has not been published under the authority of the W3C,WAI, or UAWG.
This glossary is normative.
Web content that user agents canprogrammatically determine is usable in place of other content that some peopleare not able to access. Alternative content fulfills essentially the samefunction or purpose as the original content. There are several general types ofalternative content:
text alternative for non-text content: Text that isprogrammatically associated with non-text content or referred to fromtext that is programmatically associated with non-text content. For example, animage of a chart might have two text alternatives: a short text alternative anda described-by relationship to a nearby paragraph that more fully describes thecontent of the chart.
alternative for time-based media: Web content that serves the samefunction or purpose as one or more tracks in a time-based media presentation.This includes alternatives for audio such as captions and sign languageinterpretation, and alternatives for video such as audio descriptions and extended audio descriptions. Another form oftime-based media alternative is a correctly sequenced text description oftime-based visual and auditory information that also is capable of achievingthe outcomes of any interactivity in the time-based presentation.
text alternatives for text content: Text that isprogrammatically associated with certain types of text content to provideexpanded information. For example, an abbreviation (or acronym) can provide anexpansion of the shortened word or initialized words (<abbr title="UserAgent Accessibility Guidelines">UAAG</abbr>).
media alternative for text: Media that presentsno more information than is already presented in text (directly or via textalternatives). A media alternative for text is provided for people who benefitfrom alternate representations of text. Media alternatives for text can beaudio-only, video-only (including sign-language video), or audio-video.
Note: According to WCAG2.0, alternative content may or may not be programmatically determinable (e.g.,a short description for an image might appear in the image's descriptionattribute or within text near the image). However, UAAG 2.0 adds the programmatically available condition becausethis is the only type of alternative content that user agents can recognize.
Graphical content rendered toautomatically change over time, giving the user a visual perception ofmovement. Examples include video, animated images, scrolling text, programmaticanimation (e.g. moving or replacing rendered objects).
A mechanism that defines how communication can takeplace between applications.
For the purpose of UAAG 2.0 conformance, assistivetechnology meets the following criteria:
1. Relies on services (such asretrieving web resources and parsing markup) provided by oneor more host user agents.
2. Communicates data and messages withhost user agents by monitoring and using APIs.
3. Provides services beyond thoseoffered by the host user agents to meet the requirements of users withdisabilities. Additional services include alternative renderings (e.g. assynthesized speech or magnified content), alternative input methods (e.g.voice), additional navigation or orientation mechanisms, and contenttransformations (e.g. to make tables more accessible).
Examples of assistive technologies that are importantin the context of UAAG 2.0 include the following:
Screen magnifiers, which are used bypeople with visual disabilities to enlarge and change colors on the screen toimprove the visual readability of rendered text and images.
Screen readers, which are used bypeople who are blind or have reading disabilities to read textual informationthrough synthesized speech or braille displays.
Voice recognition software, which isused by some people who have physical disabilities to simulate the keyboard andmouse.
Alternative keyboards, which areused by some people with physical disabilities to simulate the keyboard andmouse.
Alternative pointing devices, whichare used by some people with physical disabilities to simulate mouse pointingand button activations.
The technology of sound transmission. Audio can becreated synthetically (including speech synthesis), streamed from a live source(e.g. a radio broadcast), or recorded from real world sounds. There can bemultiple audio tracks in a presentation.
A type of alternative content that takes the formof narration added to the audio to describe important visual details that cannot beunderstood from the main soundtrack alone. Audio description of video provides informationabout actions, characters, scene changes, on-screen text, and other visualcontent. In standard audio description, narration is added during existingpauses in dialogue.
All or part of the audio portion of a presentation (e.g. each instrument canhave a track, or each stereo channel can have a track).
A person who works alone or collaboratively to createcontent (e.g. content author,designer, programmer, publisher, tester).
Printing devices that are identified as available toapplications via the platform.
A type of alternative content that takes the formof text presented and synchronized with time-based media to provide not onlythe speech, but also non-speech information conveyed through sound, includingmeaningful sound effects and identification of speakers. In some countries, theterm "subtitle" is used to refer to dialogue only and"captions" is used as the term for dialogue plus sounds and speakeridentification. In other countries, "subtitle" (or its translation)is used to refer to both.
closed captions: Captions that canbe turned on and off. The captions requirements of UAAG 2.0 assume that theuser agent can recognize the captions as such.
Note: Other terms that include the word"caption" can have different meanings. For instance, a "tablecaption" is a title for a table, often positioned graphically above orbelow the table.
Actions made by users to control the user agent. These include:
direct commands: Commands that applyto a specified item (e.g. button) or action (e.g. save function), regardless ofthe current focus location. Also see keyboard command
sequential navigation commands (sometimes called"logical navigation commands" or "linear navigationcommands"): Commands that move focus forwards and backwards through a listof items. The element list being navigated can be the list of all elements orjust a subset (e.g. the list of headers, the list of links).
Information and sensory experience to be communicatedto the user by means of a user agent, including code ormarkup that defines the content's structure, presentation, and interactions.
When interacting with a time-based media presentation,a continuous scale allows user (or programmatic) action to set the activeplayback position to any time point on the presentation time line. Thegranularity of the positioning is determined by the smallest resolvable timeunit in the media timebase.
using a direct command
A platform- and language-neutral interface thatallows programs and scripts to dynamically access and update the content,structure and style of documents. The document can be further processed and theresults of that processing can be incorporated back into the presented page.Overview of DOM-related materials: http://www.w3.org/DOM/#what.
Any information that supports the use of a user agent. This informationcan be provided electronically or otherwise and includes help, manuals,installation instructions, tutorials, etc. Documentation can be accessed invarious ways (e.g. as files included in the installation, available on theweb).
Note: The level of technical detail in documentation for users should match thetechnical level of the feature. For example, user documentation for a browser'szoom function should not refer users to the source code repository for thatbrowser.
Primarily, a syntactic construct of a document typedefinition (DTD) for its application. This is the sense employed by the XML 1.0specification ([XML], section 3). UAAG 2.0also uses the term "element" more generally to refer to any discreteunit within the content (e.g. a specific image, video, sound, heading, list, orlist item).
enabled element: An element with associatedbehaviors that can be activated through the user interface or through an API. The set of elements that a useragent enables is generally derived from, but is not limited to, the set of elements defined by implemented markuplanguages.
element type: A category of elements (such as images, videos,sounds, first level headings, lists, or list items).
User agents often perform a task when an event havinga particular "event type" occurs, including a user interface event, achange to content, loading of content, or a request from the operating environment. Some markup languages allowauthors to specify that a script, called an event handler, be executed when an event of agiven type occurs. An event handler is explicitly associatedwith an element through scripting,markup or the DOM.
An interaction by the user through the UA user interface, the focus, or the selection. User requests are made, forexample, through user agent user interface controls and keyboard commands. Some examples of explicit userrequests include when the user selects "New viewport," responds"yes" to a prompt in the user agent's user interface, configures theuser agent to behave in a certain way, or changes the selection or focus withthe keyboard or pointing device. Note: Users can make errors wheninteracting with the user agent. For example, a user can inadvertently respond"yes" to a prompt instead of "no." This type of error isstill considered an explicit user request.
The location where input will occur if a viewport is active. Examplesinclude:
keyboard focus: The screen locationwhere keyboard input will occur ifa viewport is active.
pointing device focus: The screen locationwhere pointer input will occur ifa viewport is active. There can be multiple pointing device foci for examplewhen using a screen sharing utility there is typically one for the user'sphysical mouse and one for the remote mouse.
The active input focus is in the activeviewport. The inactive input focus is in the inactiveviewport. Focus is typically indicated by a focus cursor.
pointer: Indicator showing where pointingdevice input will occur. The indicator can be moved with a pointing device oremulator such as a mouse, pen tablet, keyboard-based mouse emulator,speech-based mouse commands, or 3-D wand. A pointing device click typicallymoves the input focus to the pointerlocation. The indicator can change to reflect different states. Whentouchscreens are used, the "pointing device" is a combination of thetouchscreen and the user's finger or stylus. On most touchscreen systems thereis no pointer (on-screen visual indication).
Cursors are active when in the active viewport, andinactive when in an inactive viewport.
Any element capable of having input focus (e.g. a link, textbox, or menu item). In order to be accessible and fully usable, every focusableelement should take keyboard focus, and ideally wouldalso take pointer focus.
A setting is one that applies to the entire user agent or all content beingrendered by it, rather than to a specific feature within the user agent or aspecific document being viewed.
Information (e.g. text, colors, graphics, images, or animations) rendered for visualconsumption.
Emphasis indicated through the user interface. Forexample, user agents highlight contentthat is selected, focused, or matched by a search operation. Graphicalhighlight mechanisms include dotted boxes, changed colors or fonts,underlining, adjacent icons, magnification, and reverse video. Synthesizedspeech highlight mechanisms include alterations of voice pitch and volume (i.e. speech prosody). User interface items can also be highlighted, for examplea specific set of foreground and background colors for the title bar of theactive window. Content that is highlighted may or may not be a selection.
Pictorial content that is static (i.e. not moving orchanging). Also see animation.
The letter, symbol and command keys or key indicatorsthat allow a user to control a computing device. Assistive technologies havetraditionally relied on the keyboard interface as a universal, or modalityindependent interface. In this document references to keyboard include keyboardemulators and keyboard interfaces that make use of thekeyboard's role as a modality independent interface (see Modality Independence). Keyboard emulatorsand interfaces can be used on devices which do not have a physical keyboard,such as mobile devices based on touchscreen input.
Keyboard interfaces are programmatic servicesprovided by many platforms that allow operation in a device independent manner.A keyboard interface can allow keystroke input even if particular devices donot contain a hardware keyboard (e.g. a touchscreen-controlled device can havea keyboard interface built into its operating system to support onscreen keyboards aswell as external keyboards that can be connected).
Note: Keyboard-operatedmouse emulators, such as MouseKeys, do not qualify as operation through akeyboard interface because these emulators use pointing device interfaces, notkeyboard interfaces.
A key or set of keys that are tied to a particular UIcontrol or application function, allowing the user to navigate to or activatethe control or function without traversing any intervening controls (e.g.CTRL+"S" to save a document). It is sometimes useful to distinguishkeyboard commands that are associated with controls that are rendered in thecurrent context (e.g. ALT+"D" to move focus to the address bar) fromthose that can be able to activate program functionality that is not associatedwith any currently rendered controls (e.g. "F1" to open the Helpsystem). Keyboard commands can be triggered using a physical keyboard orkeyboard emulator (e.g. on-screen keyboard or speech recognition). (See Modality Independent Controls). Sequential keyboard commands require multiplekeystrokes to carry out an action (e.g. a series of Tab or arrow pressesfollowed by Enter, or a sequence like ALT-F, V to drop down a File menu andchoose Print Preview).
normative, informative (non-normative)
Required (or not required) for conformance. Abilitiesidentified as "normative" are required for conformance (noting that one can conform in avariety of well-defined ways to UAAG 2.0). Abilities identified as"informative" (or, "non-normative") are never required forconformance.
To make the user aware of events or status changes.Notifications can occur within the UA user interface (e.g. a status bar) or within thecontent display. Notifications can be passive and not require useracknowledgment, or they can be presented in the form of a prompt requesting a userresponse (e.g. a confirmation dialog).
To render a visual element in the same screen spaceas a second visual element in a way that prevents the second visual elementfrom being visually perceived.
Note: The use of transparent backgrounds for the overlaying visual element(e.g., video captions) is an acceptable technique for reducing obscuration, ifspace is available.
The software environment that governs the useragent's operation, whether it is an operating system or a programming languageenvironment such as Java.
Software that supports a device's basic functions,such as scheduling tasks, executing applications, and managing hardware andperipherals.
Note: Many operatingsystems mediate communication between executing applications and assistive technology via a platform accessibility service.
When one configuration or behavior preferenceprevails over another. Generally, the requirements of UAAG 2.0 involve userpreferences prevailing over author preferences and user agent default settingsand behaviors. Preferences can be multi-valued in general (e.g. the userprefers blue over red or yellow), and include the special case of two values(e.g. turn on or off blinking text content).
Content generated by the user agent to replaceauthor-supplied content. A placeholder can be generated as the result of a userpreference (e.g. to not render images) or as repair content (e.g. when an image cannot be found).A placeholder can be any type of content, including text, images, and audiocues. A placeholder should identify the technology of the replaced object.
The software and hardware environment(s) within whichthe user agent operates. Platformsprovide a consistent operational environment. There can be layers of softwarein an hardware architecture and each layer can be considered a platform. Nativeplatforms include desktop operating system (e.g. Linux, Mac OS, Windows,etc.), mobile operating systems (e.g. Android, Blackberry, iOS, Windows Phone,etc.), and cross-OS environments (e.g. Java). Web-based platforms are otheruser agents. User agents can employ server-based processing, such as webcontent transformations, text-to-speech production, etc.
Note 1: A user agent caninclude functionality hosted on multiple platforms (e.g. a browser running onthe desktop can include server-based pre-processing and web-baseddocumentation).
Note 2: Accessibilityguidelines for developers exist for many platforms.
A programmatic interface that is engineered toenhance communication between mainstream software applications and assistivetechnologies (e.g. MSAA, UI Automation, and IAccessible2 for Windowsapplications, AXAPI for Mac OSX applications, Gnome Accessibility Toolkit APIfor GNOME applications, Java Access for Java applications). On some platformsit can be conventional to enhance communication further by implementing a DOM.
see user agent
The position in rendered content that the user is presumed to beviewing. The dimensions of the point of regard can vary. For example,it can bea two-dimensional area (e.g. content rendered through a two-dimensionalgraphical viewport), or a point (e.g. a moment during an audio rendering or acursor position in a graphical rendering), or a range of text (e.g. focusedtext), or a two-dimensional area (e.g. content rendered through atwo-dimensional graphical viewport). The point of regard is almost alwayswithin the viewport, but it can exceed the spatial or temporal dimensions of the viewport (seethe definition of rendered content for more information about viewportdimensions). The point of regard can also refer to a particular moment in timefor content that changes over time (e.g. an audio-only presentation). Useragents can determine the point of regard in a number of ways, including basedon viewport position in content, keyboard focus, and selection.
see focus cursor
A named and persistent representation of userpreferences that can be used to configure a user agent. Preferences includeinput configurations, style preferences, and natural language preferences. In operating environments with distinct user accounts,profiles enable users to reconfigure software quickly when they log on. Userscan share their profiles with one another. Platform-independent profiles areuseful for those who use the same user agent on different devices.
Information that is encoded in a way that allowsdifferent software, including assistive technologies, to extract and use the informationrelying on published, supported mechanisms, such as, platform accessibilityservices, APIs, or the document object models (DOM). For web-based userinterfaces, this means ensuring that the user agent can pass on the information (e.g.through the use of WAI-ARIA). Something is programmatically available if theentity presenting the information does so in a way that is explicit andunambiguous, in a way that can be understood without reverse-engineering orcomplex (and thus potentially fallible) heuristics, and only relying on methodsthat are published, and officially supported by the developers of the softwarebeing evaluated.
Any user agent-initiated request for a decision orpiece of information from a user.
A user agent renders a document by applyingformatting algorithms and style information to the document's elements.Formatting depends on a number of factors, including where the document isrendered (e.g. on screen, on paper, through loudspeakers, on a braille display,on a mobile device). Style information (e.g. fonts, colors, synthesized speechprosody) can come from the elements themselves (e.g. certain font and phraseelements in HTML), from stylesheets, or from user agent settings. For thepurposes of these guidelines, each formatting or style option is governed by aproperty and each property can take one value from a set of legal values.Generally in UAAG 2.0, the term "property" has themeaning defined in CSS 2.1 Conformance ([CSS21], ). A reference to"styles" in UAAG 2.0 means a set of style-related properties.
default value: The value given to a property by a user agent at installation.
Information or events that can be identifiedunambiguously by user agents.
recognized content: Information that isencoded within content in a way that can be unambiguously recognized by useragents. Authors encode information in many ways, including in markuplanguages, style sheet languages, scripting languages, and protocols. When theinformation is encoded in a manner that allows the user agent to process itwith certainty, the user agent can "recognize" the information. Forinstance, HTML allows authors to specify a heading with the H1 element, so a useragent that implements HTML can recognize that content as a heading. If theauthor creates a heading using a visual effect alone (e.g. just by increasingthe font size), then the author has encoded the heading in a manner that doesnot allow the user agent to recognize it as a heading. Some requirements ofUAAG 2.0 depend on content roles, content relationships, timing relationships,and other information supplied by the author. These requirements only applywhen the author has encoded that information in a manner that the user agentcan recognize. See the section on conformance for more information aboutapplicability. User agents will rely heavily on information that the author hasencoded in a markup language or style sheet language. Behaviors, style, meaningencoded in a script, and markup in an unfamiliar XMLnamespace can not be recognized by the user agent as easily or at all.
recognized actions: Actions or eventsthat can be unambiguously identified by a user agent. This can include actionsor events initiated by users, scripts, add-ons, or other sources. For example,if the keyboard focus is on a web page when the user presses a key, the useragent can recognize the keystroke and can act upon it. If the keyboard focus ison an embedded media player when the user presses a key, the host user agentmay or may not be able to detect the keystroke, depending on the embeddingarchitecture. Similarly, when the user activates an INPUT element withtype="submit", the user agent will recognize this as a formsubmission action and carry out the proper interchange with the server.However, if a page includes a custom control that looks like a button labeled"Submit**" but whose actions are entirely handled by anauthor-provided script, the user agent would not be able to recognize the useraction as equivalent to a form submission. Actions such as opening of newbrowser window would always be implemented by the user agent, so the actionwould be recognized regardless of whether it was initiated by the user clickinga button or by a script calling a browser function.
Time intervals for navigating media relative to thecurrent point (e.g. move forward 30 seconds). When interacting with atime-based media presentation, a user can find it beneficial to move forward orbackward via a time interval relative to their current position. For example, auser can find a concept unclear in a video lecture and elect to skip back 30seconds from the current position to review what had been described. Relativetime units can be preset by the user agent, configurable by the user, and/orautomatically calculated based upon media duration (e.g. jump 5 seconds in a30-second clip, or 5 minutes in a 60-minute clip). Relative time units aredistinct from absolute time values such as the 2 minute mark, the half-waypoint, or the end.
The presentation generated by the user agent based onthe author supplied code. This includes:
content specified by the author
dynamic content created or alteredby scripts
content inserted by the user agent(e.g. repair text and security warnings on links)
content inserted by style sheets ormarkup (e.g. number or letter preceding an ordered list item, the CSS contentproperty)
rendered text: Text content that isrendered in a way that communicates information about the charactersthemselves, whether visually or as synthesized speech.
Content generated by the user agent to correct anerror condition. "Repair text" refers to the text portion of repair content. Errorconditions that can lead to the generation of repair content include:
Erroneous or incomplete content(e.g. ill-formed markup, invalid markup, or missing alternative content that is required by formatspecification);
Missing resources for handling orrendering content (e.g. the user agent lacks a font family to display somecharacters, or the user agent does not implement a particular scriptinglanguage).
Note: UAAG 2.0 does not require useragents to include repair content in the document object. Repair content inserted in thedocument object should conform to the Web Content Accessibility Guidelines 2.0 [WCAG20]. For more information about repairtechniques for web content and software, refer to "Implementing ATAG2.0" [ATAG20-IMPLEMENTING].
A publication of the Internet Engineering Task Force(IETF) on Key words for use in Request for Comments (RFC) to IndicateRequirement Levels. The key words are "MUST", "MUST NOT","REQUIRED", "SHALL", "SHALL NOT","SHOULD", "SHOULD NOT", "RECOMMENDED","MAY", and "OPTIONAL" . This information is provided forexplanation. UAAG 2.0 does not use these terms as defined in RFC 2119.
Instructions to create dynamic web content that arewritten in a programming (scripting) language. In guidelines referring to thewritten (natural) language of content, as referenced in Unicode [UNICODE]), script can also refer to "acollection of symbols used to represent textual information in one or morewriting systems". Information encoded in (programming) scripts can bedifficult for a user agent to recognize. For instance, a user agent is notexpected to recognize that, when executed, a script will calculate a factorial.The user agent will be able to recognize some information in a script by virtueof implementing the scripting language or a known program library (e.g. theuser agent is expected to recognize when a script will open a viewport orretrieve a resource from the web).
A user agent mechanism foridentifying a (possibly empty) range of content that will be the implicitsource or target for subsequent operations. The selection can be used for avariety of purposes, including for cut-and-paste operations, to designate aspecific element in a document for the purposes of a query, and as anindication of point of regard (e.g. the matched results of asearch can be automatically selected). The selection should be highlighted in a distinctivemanner. On the screen, the selection can be highlighted in a variety of ways,including through colors, fonts, graphics, and magnification. When renderedusing synthesized speech, the selection can be highlighted through changes inpitch, speed, or prosody.
Properties whose values determine the presentation(e.g. font, color, size, location, padding, volume, synthesized speech prosody)of content elements as they are rendered (e.g. onscreen, via loudspeaker, viabraille display) by user agents. Style propertiescan have several origins:
user agent default styles: The default styleproperty values applied in the absence of any author or user styles. Some web content technologies specify a defaultrendering; others do not.
author styles: Style propertyvalues that are set by the author as part of the content (e.g. in-line styles, author style sheets).
user styles: Style property values that are setby the user (e.g. via user agent interface settings, user style sheets).
A mechanism for communicating style property settings for webcontent, in which the style property settings are separable from other contentresources. This separation allows author style sheets to be toggled or substituted,and user style sheets defined to apply to more than one resource. Style sheet web content technologies include CascadingStyle Sheets (CSS) and Extensible Stylesheet Language (XSL).
author style sheet: Style sheetsspecified by the author, resulting in author styles.
The act of time-coordinating two or more presentationcomponents (e.g. a visual track with captions,several tracks in a multimedia presentation). For authors, the requirement tosynchronize means to provide the data that will permit sensibletime-coordinated rendering by a user agent. For example, web content developerscan ensure that the segments of caption text are neither too long nor tooshort, and that they map to segments of the visual track that are appropriatein length. For user agent developers, the requirement to synchronize means topresent the content in a sensible time-coordinated fashion under a wide rangeof circumstances including technology constraints (e.g. small text-onlydisplays), user limitations (e.g. slow reading speeds, large font sizes, highneed for review or repeat functions), and content that is sub-optimal in termsof accessibility.
A sequence of characters that are programmatically available, where the sequence is expressingsomething in human language.
non-text content: Any content that isnot a sequence of characters that can be programmatically determined or wherethe sequence is not expressing something in human language Note: This includesASCII Art (which is a pattern of characters), emoticons, leetspeak (which usescharacter substitution), and images representing text.
A type of alternative content that takes the form oftext equivalents of audio information (e.g. an audio-only presentation or the audio track of a movie or other animation). Atext transcript provides text for both spoken words and non-spoken sounds suchas sound effects. Text transcripts make audio information accessible to peoplewho have hearing disabilities and to people who cannot play the audio. Texttranscripts are usually created by hand but can be generated on the fly (e.g.by voice-to-text converters).
Any software that retrieves, renders and facilitatesend user interaction with web content. UAAG 2.0 identifies the following useragent architectures:
platform-based user agent, native user agent: User agents thatrun on non-web platforms (operating systems and cross-OS platforms, such asJava) and perform content retrieval, rendering and end-user interactionfacilitation themselves (e.g. Firefox, Internet Explorer, Chrome, Opera,Windows Media Player, QuickTime Pro, RealPlayer).
embedded user agent, plug-in: User agents that"plug-in" to other user agents or applications (e.g. media playerplug-in for a web browser, web view component). Embedded user agents canestablish direct connections with the platform (e.g. communication via platformaccessibility services). See user agent add-on.
web-based user agent: User agents that have userinterfaces that are implemented using web content technologies and are accessedby users via a user agent. Web-based user agents transform content into webcontent technologies that the host user agent can render (e.g.web-based ePubreader, web-based video player).
Note 1: Success criteria may also be met byother software. See the applicability notes on Add-ons (Extensions and Plug-ins) and Relationship with operating systemor platform.
Note 2: Many web applicationsretrieve, render and facilitate interaction with very limited data sets (e.g.online ticket booking). In such cases, WCAG 2.0, without UAAG 2.0, can beappropriate for assessing the application's accessibility.
Examples of software that are generally considered user agents under UAAG 2.0:
Desktop web browsers (e.g. InternetExplorer, Firefox, Chrome, Safari, Opera)
Mobile web browsers (e.g. Firefox,Chrome, Safari, Android Browser, Opera Mini, Atomic Web, Puffin)
Browser plug-ins (e.g. QuickTimePlug-in for Firefox, Acrobat Reader Plug-in for Internet Explorer, ShockwavePlug-in for Chrome)
Web view components (e.g. WebkitWebview component, Web Tools Platform Plug-in for Eclipse, UIWebView for iOS)
Authoring tools that render the webcontent being edited (e.g. Word, Dreamweaver, HTML-Kit)
Examples of software that are not considered useragents under UAAG 2.0 (in all cases, WCAG 2.0 still applies if the software isweb-based):
Operating environments or softwarebundles that include platform-based user agents (e.g. Windows, OS X, KDE, iOS),though the included user agents themselves are covered by UAAG 2.0.
General-purpose platforms ortoolkits that don't use web technologies, even though they can be used by useragents for other purposes (e.g. GNOME, KDE, .NET Framework/CLR).
Narrow-purpose platform-based or webapplications (e.g. online ticket booking applications).
Authoring tools that only display asource view of the web content being edited (e.g. Notepad, Vim).
Software installed into a user agent that adds one ormore additional features that modify the behavior of the user agent. Extensionsand plug-ins are types of add-ons. See embedded user agent and applicability note on Add-ons (Extensions and Plug-ins) for additionalinformation. Two common capabilities for user agent add-ons are the ability to
modify the content before the user agent renders it(e.g. to add highlights if certain types of alternative content are present),and
modify the user agent's own user interface (e.g. add a headingsview).
For the purposes of UAAG 2.0, the user interfaceincludes both:
user agent user interface (UA user interface): The controls (e.g. menus,buttons, prompts, native audio/video player controls, and othercomponents for input and output) and mechanisms (e.g. selection and focus)provided by the user agent that are not createdon the basis of the author-supplied content. The UA user interface can include extensions that become part ofthe UA user interface (e.g. toolbars, additional menus).
content user interface: The user interfacethat emerges from the user agent rendering of the author-supplied content. Itincludes all rendered content (e.g. text, headings, enabled elements, disabled elements, author-suppliedaudio/video controls).
Note: There can be a mixof recognized and unrecognizeduser interface controls depending on the author-supplied content.
This document distinguishes UA user interface andcontent user interface only where required for clarity.
The technology of moving pictures or images. Videocan be made up of animated or photographic images, or both.
A user interface function that lets users interactwith web content. UAAG 2.0 recognizes a variety of approaches to presenting thecontent in a view, including:
rendered view: A view where content is presented such that it isrendered, played or executed. There are two sub-types:
In conventionally rendered views thecontent is rendered, played or executed according to the web content technologyspecification. This is the default view of most user agents.
In unconventionally rendered viewsthe content is rendered quite differently than specified in the technologyspecification (e.g. rendering an audio file as a graphical wavefront).
source view: A view where the web content is presented without being rendered, playedor executed. The source view can be plain text (i.e. "View Source")or it can include some other organization (e.g. presenting the markup in atree).
outline view: A view where only a subset of the rendered contentis presented, usually composed of labels or placeholders for importantstructural elements. The important structural elements will depend on the webcontent technology, but can include headings, table captions, and contentsections.
Note: A view can be visual, audio, ortactile.
A mechanism for presenting only part of a visual ortactile view to the user via ascreen or tactile display. There can be multiple viewports on to the sameunderlying view (e.g. when a split-screen is used to present the top and bottomof a document simultaneously) and viewports can be nested (e.g. a scrollingframe located within a larger document). When the viewport is smaller than theview it is presenting, some of the view will not be presented. Mechanisms aretypically provided to move the view or the viewport such that all of the viewcan be brought into the viewport (e.g. scrollbars).
Note: In UAAG 1.0viewports were defined as having a temporal dimension. In UAAG 2.0, this is notthe case. Since audio content is inherently time-based, audio viewports areexcluded.
top-level viewport: A viewport that isnot contained within another viewport of a platform-based user agent. Web-baseduser agents are always displayed inside another viewport, and therefore arenever top-level viewports. A popular browser implementation is to provide awindow that includes some UA user interface elements (e.g., menus) and a seriesof tabbed panels, each of which contains additional UA user interface elements(e.g., address bar, bookmarks, back/forward buttons) and a top-level viewportfor rendering a view of the addressed web resource.
The onscreen size of a viewport, or the temporalduration of a viewport displaying time-based media. When the dimensions(spatial or temporal) of rendered content exceed the dimensions of theviewport, the user agent provides mechanisms such as scroll bars and advanceand rewind controls so that the user can access the rendered content"outside" the viewport (e.g. when the user can only view a portion ofa large document through a small graphical viewport, or when audio content hasalready been played).
Content consisting exclusively of one or more visual tracks presented concurrently or in series(e.g. a silent movie is an example of a visual-only presentation).
Content rendered through a graphical viewport. Visual objectsinclude graphics, text, and visual portions of movies and other animations. Avisual track is a visual object that is intended as a whole or partialpresentation. A visual track does not necessarily correspond to a singlephysical object or software object.
A device (hardware and software) that interpretsvoice markup languages to generate voice output, interpret voice input, and possiblyaccept and produce other modalities of input and output. Definition from"Introduction and Overview of W3C Speech Interface Framework" [VOICEBROWSER].
Anything that can be identified by a Uniform ResourceIdentifier (URI).
This section is informative.
For the mostup-to-date information, see "Referencing and Linking to WAI Guidelines andTechnical Documents" at <http://www.w3.org/WAI/intro/linking.html>.
There are tworecommended ways to refer to the "User Agent Accessibility Guidelines2.0" (and to W3C documents in general):
- References to a specific version of "User Agent Accessibility Guidelines 2.0." For example, use the "this version" URI to refer to the current document:
- References to the latest version of "User Agent Accessibility Guidelines 2.0." Use the "latest version" URI to refer to the most recently published document in the series:
The top of UAAG 2.0includes the relevant catalog metadata for specific references (includingtitle, publication date, "this version" URI, editors' names, andcopyright information).
An XHTML 1.0paragraph including a reference to this specific document might be written:
"User Agent Accessibility Guidelines 2.0,"</a></cite>
J. Allan, K. Ford, J. Spellman, eds.,
W3C Recommendation, http://www.w3.org/TR/ATAG20/.
The <a href="http://www.w3.org/TR/ATAG20/">latestversion</a> of this document is available at http://www.w3.org/TR/ATAG20/.</p>
For very generalreferences to this document (where stability of content and anchors is notrequired), it can be appropriate to refer to the latest version of thisdocument. Other sections of this document explain how to build a conformance claim.
This section is informative.
For the latestversion of any W3C specification please consult the list of W3C Technical Reports at http://www.w3.org/TR/. Somedocuments listed below may have been superseded since the publication of UAAG2.0.
Note: In UAAG 2.0,bracketed labels such as "[WCAG20]" link to the corresponding entriesin this section. These labels are also identified as references through markup.
"Accessible Rich Internet Applications(WAI-ARIA) 1.0" J. Craig, M. Cooper, eds., 20 March 2014. This W3CRecommendation is http://www.w3.org/TR/2014/REC-wai-aria-20140320/
"Authoring Tool Accessibility Guidelines (ATAG)2.0," J. Richards, J. Spellman, J. Treviranus, eds., 24September 2015. This W3C Recommendation ishttp://www.w3.org/TR/2015/REC-ATAG20-20150924/
"Implementing ATAG 2.0" J. Richards, J.Spellman, J. Treviranus, eds., 24 September 2015. This W3C Note ishttp://www.w3.org/TR/2015/NOTE-IMPLEMENTING-ATAG20-20150924/.
"Character Model for the World Wide Web," M. Dürst and F.Yergeau, eds., 30 April 2002. This W3C Working Draft ishttp://www.w3.org/TR/2002/WD-charmod-20020430/. The latest version is available athttp://www.w3.org/TR/charmod/.
"Cascading Style Sheets Level 2 Revision 1 (CSS2.1) Specification," B. Bos, T. Celik, I. Hickson, H.Lie, eds., 07 June 2011. This W3C Recommendation ishttp://www.w3.org/TR/2011/REC-CSS2-20110607/.
"Document Object Model (DOM)Level 2 HTML Specification," J. Stenback, P. LeHégaret, A. Le Hors, eds., 8 November 2002. This W3C Proposed Recommendation ishttp://www.w3.org/TR/2002/PR-DOM-Level-2-HTML-20021108/. The latest version is available athttp://www.w3.org/TR/DOM-Level-2-HTML/.
"HTML 4.01 Recommendation," D. Raggett, A. LeHors, and I. Jacobs, eds., 24 December 1999. This W3C Recommendation ishttp://www.w3.org/TR/1999/REC-html401-19991224/.
"Hypertext Transfer Protocol — HTTP/1.1," J. Gettys, J. Mogul,H. Frystyk, L. Masinter, P. Leach, T. Berners-Lee, June 1999.
"XML Media Types," M. Murata, S. St.Laurent, D. Kohn, January 2001.
"Synchronized Multimedia Integration Language(SMIL) 1.0 Specification," P. Hoschka, ed., 15June 1998. This W3C Recommendation ishttp://www.w3.org/TR/1998/REC-smil-19980615/.
"Synchronized Multimedia Integration Language(SMIL 2.0) Specification," J. Ayars, et al.,eds., 7 August 2001. This W3C Recommendation ishttp://www.w3.org/TR/2001/REC-smil20-20010807/.
"Scalable Vector Graphics (SVG) 1.0Specification," J. Ferraiolo, ed., 4 September2001. This W3C Recommendation is http://www.w3.org/TR/2001/REC-SVG-20010904/.
"User Agent Accessibility Guidelines 1.0," I. Jacobs, J.Gunderson, E. Hansen, eds.17 December 2002. This W3C Recommendation isavailable at http://www.w3.org/TR/2002/REC-UAAG10-20021217/.
Information about UAAG 1.0 conformance icons and their usage is available athttp://www.w3.org/WAI/UAAG10-Conformance.
An appendix to UAAG 1.0 provides a summary of the goals andstructure of User Agent Accessibility Guidelines 1.0.
"Techniques for User Agent Accessibility Guidelines 1.0," I. Jacobs, J.Gunderson, E. Hansen, eds. The latest draft of the techniques document isavailable at http://www.w3.org/TR/UAAG10-TECHS/.
The Unicode Consortium. The Unicode Standard, Version 8.0.0, (MountainView, CA: The Unicode Consortium, 2015. ISBN 978-1-936213-10-8)
"Introduction and Overview of W3C SpeechInterface Framework," J. Larson, 4 December 2000. ThisW3C Working Draft is http://www.w3.org/TR/2000/WD-voice-intro-20001204/. The latest version is available athttp://www.w3.org/TR/voice-intro/. UAAG 2.0 includes references to additionalW3C specifications about voice browser technology.
"World Wide Web Consortium ProcessDocument," I. Jacobs ed. The 19 July 2001version of the Process Document ishttp://www.w3.org/Consortium/Process-20010719/. The latest version is available athttp://www.w3.org/Consortium/Process/.
"Web Content Accessibility Guidelines (WCAG) 2.0" B. Caldwell, M.Cooper, L. Guarino Reid, G. Vanderheiden, eds., 8 December 2008. This W3CRecommendation is http://www.w3.org/TR/2008/REC-WCAG20-20081211/. The latest version is available athttp://www.w3.org/TR/WCAG20/. Additional format-specific techniques documentsare available from this Recommendation.
"Techniques for Web Content Accessibility Guidelines 2.0," B. Caldwell, M.Cooper, L. Guarino Reid, G. Vanderheiden, eds., 8 December 2008. This W3C Noteis http://www.w3.org/TR/2010/NOTE-WCAG20-TECHS-20101014/. The latest version is available athttp://www.w3.org/TR/WCAG20-TECHS/. Additional format-specific techniquesdocuments are available from this Note.
"Website Accessibility Conformance EvaluationMethodology (WCAG-EM) 1.0" E. Velleman, S.Abou-Zahra, eds., 26 February 2013. This is an informative draft of a WorkingGroup Note. The latest version is available athttp://www.w3.org/TR/WCAG-EM/
Guidance on Applying WCAG 2.0 to Non-Web Information and CommunicationsTechnologies (WCAG2ICT) M. Cooper, P. Korn, A. Snow-Weaver,G. Vanderheiden, eds., 5 September 2013. This document is available in an expandable / collapsible alternateversion in which the “Intent” sections copied fromUnderstanding WCAG 2.0 are hidden and individually expandable, for easierreading.
"Web Characterization Terminology andDefinitions Sheet," B. Lavoie, H. F. Nielsen, eds., 24May 1999. This is a W3C Working Draft that defines some terms to establish acommon understanding about key Web concepts. This W3C Working Draft ishttp://www.w3.org/1999/05/WCA-terms/01.
"XML Accessibility Guidelines 1.0," D. Dardailler, S.Palmer, C. McCathieNevile, eds., 3 October 2001. This W3C Working Draft ishttp://www.w3.org/TR/2002/WD-xag-20021003. The latest version is available athttp://www.w3.org/TR/xag.
"Extensible Markup Language (XML) 1.0 (SecondEdition)," T. Bray, J. Paoli, C.M.Sperberg-McQueen, eds., 6 October 2000. This W3C Recommendation is http://www.w3.org/TR/2000/REC-xml-20001006.
"XHTML[tm] 1.0: The Extensible HyperText MarkupLanguage," S. Pemberton, et al., 26 January2000. This W3C Recommendation ishttp://www.w3.org/TR/2000/REC-xhtml1-20000126/.
"XML-Signature Syntax and Processing," D. Eastlake, J.Reagle, D. Solo, eds., 12 February 2002. This W3C Recommendation ishttp://www.w3.org/TR/2002/REC-xmldsig-core-20020212/.
"XML Encryption Syntax and Processing," D. Eastlake, J.Reagle, eds., 10 December 2002. This W3C Recommendation ishttp://www.w3.org/TR/2002/REC-xmlenc-core-20021210/.
- Jim Allan (Chair, Texas School for the Blind and Visually Impaired)
- Eric Hansen (Educational Testing Service)
- Greg Lowney (Invited Expert)
- Kimberly Patch (Invited Expert)
- Jan Richards ( Inclusive Design Institute, OCAD University)
- Jeanne Spellman (W3C Staff Contact)
Kelly Ford, Microsoft
Jan Richards, Inclusive Design Institute, OCADUniversity
Additional Contributors of Mobile Examples
- Kathy Walhbin
- Mark Sadecki
- Judy Brewer (W3C)
- Alan Cantor (Invited Expert)
- Wayne Dick (Invited Expert)
- Bim Egan (Royal National Institute of Blind People)
- Kelly Ford (Microsoft)
- Mark Hakkinen (Educational Testing Service)
- Simon Harper (University of Manchester)
- Sean Hayes (Microsoft)
- Dean Hudson (Apple)
- Patrick Lauke (Opera Software)
- Cathy Laws (IBM)
- Peter Parente (IBM)
- David Poehlman (Invited Expert)
- Simon Pieters (Opera Software)
- Henny Swan (Opera Software)
- Gregory Rosmaita (Invited Expert)
- David Tseng (Apple)
UAAG 2.0 would nothave been possible without the work of those who contributed to UAAG 1.0.This publication hasbeen funded in part with Federal funds from the U.S. Department of Health andHuman Services, National Institute on Disability Independent Living andRehabilitation Research (NIDILRR) under contract HHSP23301500054, andpreviously by the Department of Education's NIDILRR contracts ED05CO0039 andED-OSE-10-C-006. The content of this publication does not necessarily reflectthe views or official policies of the U.S. Department of Education or U.S.Department of Health and Human Services, nor does mention of trade names,commercial products, or organizations imply endorsement by the U.S. Government.