This section is normative.
shortened form of a word, phrase or name
Shortened form of a word, phrase or name, i.e. a general category that includes abbreviations, initialisms and acronyms.
abbreviation made from the initial letters of a name or phrase
that contains several words
NOTE : Many acronyms can be pronounced as words.
Example: NOAA is an acronym
made from the initial letters of the National Oceanic and Atmospheric Administration
in the United States.
An abbreviation made from the initial letters of a name or phrase that contains several words. Many acronyms can be pronounced as words. Defined differently in different languages. For example, NOAA is an acronym made from the initial letters of the National Oceanic and Atmospheric Administration in the United States.
activity where timing is part of the design of the activity and removal of the time dependency would change the functionality of the content
a version that provides all of the same information and functionality and is as up to date as any non-conformant content
input where the outcome of the input is different depending on
the rate of the analog movement (such as when line width varies with pen
speed
or
pressure.)
NOTE:
This phrase is used to differentiate conditions where there is no known
method for allowing keyboard control from
those situations were keyboard commands can be used.
Examples of Actions often done with a mouse but which can also be done
with a keyboard include
clicking, selecting, moving, sizing.
An Example of something wich uses analog, time-dependent input would be
a watercolor program where stroke width and opacity is a function of the
rate of movement (and/or pressure) of a 'brush'.
where the outcome of the input is different depending on the rate of the analog movement (such as when line width varies with pen speed or pressure.) This condition is used to make exceptions where there is no known method for allowing keyboard control but not allow exceptions for those situations were keyboard commands can be used for actions normally done with a mouse such as clicking, selecting, moving, sizing.
definitions of how communication may take
place between applications
NOTES :
Implementing APIs that are independent of a particular
operating environment (as are the W3C DOM Level 2 specifications) may reduce
implementation costs for
multi-platform user agents and promote the development of multi-platform assistive
technologies. Implementing conventional APIs for a particular operating environment
may reduce implementation costs for assistive technology developers who wish
to interoperate with more than one piece of software running on that operating
environment.
A "device API" defines how
communication
may
take place with an input or output device such as a keyboard, mouse, or video
card.
In this document, an "input/output API" defines
how applications or devices communicate with a user agent.
As used in this document,
input and output APIs include, but are not limited to, device APIs. Input and
output APIs also include more abstract communication interfaces than those specified
by device APIs. A "conventional
input/output API" is one that is expected to be implemented by software running on a particular
operating environment. For example, the conventional input APIs of the user agent
are for the mouse and keyboard. For touch screen devices or mobile devices, conventional
input APIs may include stylus, buttons, and voice. The graphical display and
sound card are considered conventional output devices for a graphical desktop
computer environment, and each has an associated API
picture created by a spatial arrangement of characters (typically from the 95 printable characters defined by ASCII).
a user agent that:
1. relies on services (such as retrieving Web content and parsing markup) provided
by one or more other "host" user
agents. Assistive technologies communicate data and messages with host user
agents by using and monitoring APIs.
2. provides services beyond those offered by the host user agents to meet the
requirements of users with disabilities. Additional services include alternative
renderings (e.g., as synthesized speech or magnified content), alternative input
methods (e.g., voice), additional navigation or orientation mechanisms, and content
transformations (e.g., to make tables more accessible).
-------- Assistive technology IS A NEW DEFINITION
narration added to the soundtrack to describe important visual
details that cannot be understood from the main soundtrack alone.
NOTE 1: Audio descriptions of video provide
information about actions, characters, scene changes and on-screen text.
NOTE 2: In standard audio description narration is added during
naturally-occurring pauses in dialog.
SEE ALSO Extended audio descriptions
narration added to the soundtrack to describe important visual details that cannot be understood from the main soundtrack alone. During naturally-occurring pauses in dialog, audio descriptions of video provide information about actions, characters, scene changes and on-screen text.
set of material created as a single entity by an author
Example: a collection consisting of markup, a style sheet, and a media resource (such
as an image or audio clip).
Note: This term from Glossary of Terms for Device Independence.
Some set of material created as a single entity by an author. Examples include a collection of markup, a style sheet, and a media resource, such as an image or audio clip.
Note: This term was taken verbatim from Glossary of Terms for Device Independence.
image that appears behind or to the back of the visual field
Images that appear behind or to the back of the visual field.
set of technologies assumed to be supported by, and enabled in,
user agents
NOTE 1: Baseline is used by authors to determine which technologies they
can assume are active when they build accessible content.
NOTE 2: Baseline is used by users to determine what technologies they
must have (and have turned on) in there user agents in order to have general
access to websites. (If specific websites specify what they "rely upon"
users can access those sites by simply having the technologies 'relied
upon' active in their user agents)
NOTE 3: Organizations or Governments can use Baselines to set reasonable
expectations (and limits on expectations) for what technologies their
constituents will need to have supported in their user agents.
NOTE 4: Some examples of entities
that may set baselines that an author may have to follow include the author,
a company, a customer and government entities.
Set of technologies assumed to be supported by, and enabled in, user agents in order for Web content to conform to these guidelines.
Note: Some examples of entities that may set baselines that an author may have to follow include the author, a company, a customer and government entities.
turn on and off between .5 and 3 times per second
"subtitles" that include not
only dialogue, but also sound effects and sometimes speaker identification
NOTE: Captions provide access to multimedia for people who are deaf or
hard of hearing
Synchronized transcripts of dialogue and important sounds. Captions provide access to multimedia for people who are deaf or hard of hearing.
change of user agent, viewport, or focus; or complete change of content that changes the meaning of the delivery unit.
Note: A change of content is not always a change of context. Small changes in content, such as an expanding outline or dynamic menu, do not change the context.
A change of user agent, viewport, or focus; or complete change of content that changes the meaning of the delivery unit.
Note: A change of content is not always a change of context. Small changes in content, such as an expanding outline or dynamic menu, do not change the context.
information in delivery
units that is used by the user agent to generate perceivable units.
NOTE:
This includes the code and/or markup that define the structure, presentation,
and interaction, as well as text, images, and sounds that convey information
to the end-user.
Information in the delivery unit that is used by the user agent to generate perceivable units. This includes the code and markup that define the structure, presentation, and interaction, as well as text, images, and sounds that convey information to the end-user.
help text that provides information related to the function currently being performed
set of material transferred between two cooperating web programs
as the response to a single HTTP request
EXAMPLE: A transfer might, for example, be between an origin
server and a user agent.
Note: This term was taken from Glossary of Terms for Device Independence.
A set of material transferred between two cooperating web programs as the response to a single HTTP request. The transfer might, for example, be between an origin server and a user agent.
Note: This term was taken from Glossary of Terms for Device Independence.
a sudden, unexpected situation or occurrence that requires immediate action to preserve health, safety or property
section of code that responds to an action taken by the user
(or user agent)
NOTE:
On Web pages, events are usually user actions such as
moving the mouse, typing, etc.
-
An event handler determines the response
to that action.
-
A technology specific event handler only responds to an
action by one kind of input device.
-
An abstract event handler is one which
can be activated by a variety of input devices.
A section of code that responds to an action taken by the user (or user agent). On Web pages, events are usually user actions such as moving the mouse, typing, etc. An event handler determines the response to that action. A technology specific event handler only responds to an action by one kind of input device. An abstract event handler is one which can be activated by a variety of input devices.
audio descriptions that are added to an audio/visual presentation
by pausing the video so that there is time to add addional description
NOTE:
This technique is only used
when the sense of the video would
be lost without the additional audio description.
audio descriptions that are added to an audio/visual presentation by pausing the video so that there is time to add addional description. This technique is only used when the sense of the video would be lost without the additional audio description.
A feature is a specific component of a technology, for example an element in a markup language or a function call in an Application Programming Interface. Typically, a given feature may only be available in specific versions of the technology, and thus may need to be noted explicitly in the required list.
passages or phrases in a language that is different from the language of the text immediately preceding and following in reading order
Foreign passages or phrases are passages or phrases in a language that is different from the language of the surrounding text.
outcomes achievable through user input
Performs or is able to perform one or more actions in response to user input.
sequence of flashes or rapidly changing image sequences where both the following occur:
there are more than three flashes within any one-second period.
Note: For the general flash threshold, a flash is defined as a pair of opposing changes in brightness of 10% or more of full scale white brightness, where brightness is calculated as {{0.2126 * ((R / FS) ^ 2.2) + 0.7152 * ((G / FS) ^ 2.2) + 0.0722 * ((B / FS) ^ 2.2). R, G, and B are the red, green, and blue RGB values of the color; FS is the maximum possible full scale RGB value for R, G, and B (255 for eight bit color channels); and the "^" character is the exponentiation operator}}. An "opposing change" is an increase followed by a decrease, or a decrease followed by an increase.
A sequence of flashes or rapidly changing image sequences where both the following occur:
the combined area of flashes occurring concurrently (but not necessarily contiguously) occupies more than one quarter of any 335 x 268 pixel rectangle anywhere on the displayed screen area when the content is viewed at 1024 by 768 pixels and
there are more than three flashes within any one-second period.
Note: For the general flash threshold, a flash is defined as a pair of opposing changes in brightness of 10% or more of full scale white brightness, where brightness is calculated as .2126*R + .7152*G + .0722B using linearized R, G, and B values. Linearized-X = (X/FS)^2.2 where FS is full scale (usually 255 today). An "opposing change" is an increase followed by a decrease, or a decrease followed by an increase.
words or phrases specific to a region or language that do not
mean what the dictionary definitions of the individual words say
For example,
the English phrase "he blew his stack" means that someone became very angry.
words or phrases specific to a region or language that do not mean what the dictionary definitions of the individual words say. For example, the English phrase "he blew his stack" means that someone became very angry.
A message to be sent and received,
A collection of facts or data from which inferences may be drawn,
Knowledge acquired through study, experience, or instruction
the perception of the color attributes is essential to understanding a piece of content
perception of the color attributes is essential to understanding a piece of content
shortened form of a name or phrase made from the initial letters
of words or syllables contained in that name or phrase
NOTE: Not defined in
all languages.
EXMPLES:
SNCF is a French initialism that contains the initial letters
of the Societe National des Chemins de Fer, the French national railroad.
ESP is an English initialism for extrasensory perception.
The shortened form of a name or phrase made from the initial letters of words or syllables contained in that name or phrase. Not defined in all languages. SNCF is a French initialism that contains the initial letters of the Societe National des Chemins de Fer, the French national railroad. ESP is an initialism for extrasensory perception.
information provided by the user that is not accepted
NOTE: . This
includes:
information that is required by the delivery unit but omitted by the user.
information that is provided by the user but that falls outside the required data format or values.
Any information provided by the user that is not accepted. This includes:
information that is required by the delivery unit but omitted by the user.
information that is provided by the user but that falls outside the required data format or values.
words used in a particular way by people in a particular field.
Example: The word StickyKeys is jargon from the field of assistive
technology/accessibility.
words used in a particular way by people in a particular field. For example, the word StickyKeys is jargon from the field of assistive technology/accessibility.
interface used by software to obtain keystroke input.
Note 1: Allows users to provide keystroke input to programs even if the
native technology does not contain a keyboard.
Example: A touch screen PDA had a keyboard interface built into its OS
and a connector for connecting external Keyboards. Applications on the
PDA can use the interface to obtain keyboard input from either an external
keyboard or from other applications that provide simulated keyboard output
– such as handwriting interpreters or speech to text applications with "keyboard
emulation" functionality.
Note 2: Operation of the application (or parts of the application) through
a keyboard operated mouse emulator, such as MouseKeys, does not qualify
as operation through a keyboard interface because operation of the program
is through its pointing device interface – not through its keyboard interface.
An alternate method for connecting a keyboard to the device for the purpose of generating text on devices that do not have a built-in or attached keyboard, or an internal method for generating text. Allowing control via the "keyboard interface" means that the content could be controlled through commands issued from the keyboard or by alternate methods that are capable of generating text as if a keyboard had been used. Keyboard-operated mouse emulation software, such as MouseKeys, does not qualify because it emulates a mouse interface and is not a keyboard interface.
text that identifies a component within Web content
hyperlink between the current
document and a single destination.
NOTE: "Link" refers to a
single "arc" in
the XML Linking Language (XLink) Version 1.0 specification.) Only links that are available to be activated by the user need
to meet accessibility requirements. This excludes links that are activated
automatically or programmatically.
Link refers to a hyperlink between the current document and a single destination. (Here, "link" refers to a single "arc" in the XML Linking Language (XLink) Version 1.0 specification.) Only links that are available to be activated by the user need to meet accessibility requirements. This excludes links that are activated automatically or programmatically.
time-based live presentation that contains only audio (no video and no interaction).
time-based live presentation that contains only video (no audio and no interaction).
the two or three year period of education that begins after completion of six years of school and ends nine years after the beginning of primary education.
Note: This definition is adapted from [UNESCO].
(L1 + 0.05) / (L2 + 0.05), where L1 is the luminosity of the lighter of the text and background colors, and L2 is the luminosity of the darker of the text and background colors.
The luminosity of a color is defined as 0.2126 * ((R / FS) ^ 2.2) + 0.7152 *
((G / FS) ^ 2.2) + 0.0722 * ((B / FS) ^ 2.2).
- R, G, and B are the red,
green, and blue RGB values of the color;
-
FS is the maximum possible
full scale RGB value for R, G, and B (255 for eight bit color channels);
and
-
the "^" character
is the exponentiation operator.
Note: Luminosity values can range from 0 (black) to 1 (white), and luminosity contrast ratios can range from 1 to 21.
(L1+.05) / (L2+.05) where L is luminosity and is defined as .2126*R + .7152*G + .0722B using linearized R, G, and B values. Linearized R (for example) = (R/FS)^2.2 where FS is full scale value (255 for 8 bit color channels). L1 is the higher value (of text or background) and L2 is the lower value.
process or technique for achieving a result
audio or video synchronized with another type of media and/or with time-based interactive elements
languages used by humans to communicate,
including spoken, written, and signed languages.
NOTE: Some sign languages are another form of the spoken language.
Other sign languages are a completely different language.
languages used by humans to communicate, including spoken, written, and signed languages.
mechanisms that allow the user to locate and/or move to a different piece of content
content that is not represented by a Unicode character
or sequence of Unicode characters when rendered in a user agent according
to the formal specification of the content type
NOTE:
This includes ASCII
Art, which is a pattern of characters.
non-text content content that communicates ideas, data, facts information and is not text
non-text content that is capable of performing one or more actions in response to user input and is not text
Note: This includes, but is not limited to, images used as links, image-based submit buttons, applets, and embedded programmatic objects.
non-text content that causes a sensory experience that is not purely decorative and does not primarily convey important information or perform a function
normative - required for conformance
NOTE: One may
conform in a variety of well-defined ways to this document
informative (sometimes "non-normative") - informational but does not define
a conformance requirment
----- WAS -normative
Required for conformance.
only one data structure
that can result from parsing
NOTE:
Parsing transforms markup or other code into a data structure,
usually a tree, which is suitable for later processing and which captures
the implied hierarchy of the input.
Parsing transforms markup or other code into a data structure, usually a tree, which is suitable for later processing and which captures the implied hierarchy of the input. Parsing unambiguously means that there is only one data structure that can result
relationships in the content that can be perceived from the default presentation.
relationships in the content that are necessary to perceive the organization of the content.
unit that results from a user
agent rendering the contents of a delivery unit.
NOTE:
User agents may or may not render
all information in a delivery
unit. In some cases, a single delivery unit may be rendered as multiple perceivable
units
For example, a single html file that is rendered as a set of
presentation slides. Most perceivable units contain presentation and
the means for interaction. However, for some devices such as printers,
a perceivable unit may only contain presentation.
The result of a user agent rendering the contents of a delivery unit. User agents may or may not render all information in a delivery unit. In some cases, a single delivery unit may be rendered as multiple perceivable units. For example, a single html file that is rendered as a set of presentation slides. Most perceivable units contain presentation and the means for interaction. However, for some devices such as printers, a perceivable unit may only contain presentation.
rendering of the content and structure in a form that can be perceived by the user.
six year time period that begins between the ages of five and seven, possibly without any previous education
Note: This definition is adapted from [UNESCO].
recognized by assistive technologies that support the technologies in the chosen baseline
recognized by user agents, including assistive technologies, that support the technologies in the chosen baseline
functional component, such as a link or control, that causes a change of context when activated
interface component created by the author that is in addition
to those provided by the user agent.
Example:
A checkbox function implemented in script would be a programmatic
user interface component because it provides functionality that is not
known or supported by user agents and can not be made accessible by user
agents even if the user agent complied with UAAG.
Counter Example: An HTML checkbox would
not be
a programmatic
user interface component because the author is using an interface component supported by the user agent.
An interface component created by the author that is in addition to those provided by the user agent. For example, an HTML checkbox would not be a programmatic user interface component because the author is using an interface component supported by the user agent. A checkbox function implemented in script, however, would be a programmatic user interface component because it provides functionality that is not known or supported by user agents and can not be made accessible by user agents even if the user agent complied with UAAG.
events that are live and not under the control of the author or user
A transition to or from a saturated red where both of the following occur:
the combined area of flashes occurring concurrently occupies more than one quarter of any 341 x 256 pixel rectangle anywhere on the displayed screen area when the content is viewed at 1024 by 768 pixels and
there are more than three flashes within any one-second period.
A transition to or from a saturated red where both of the following occur:
the combined area of flashes occurring concurrently occupies more than one quarter of any 335 x 268 pixel rectangle anywhere on the displayed screen area when the content is viewed at 1024 by 768 pixels and
there are more than three flashes within any one-second period.
A regular expression as defined in XML Schema Part 2: Datatypes, Appendix F.
the
outcome of their use is identical
EXAMPLE: A submit "search" button
on one delivery unit and a "find" button on another delivery unit may both have a field to enter a term and list
topics in the web site related to the term submitted. In this case they
would have same functionality but would not be labeled consistently.
Items are considered to have the same functionality if the outcome of their use is identical. For instance, a submit "search" button on one delivery unit and a "find" button on another delivery unit may both have a field to enter a term and list topics in the web site related to the term submitted. In this case they would have same functionality but would not be labeled consistently.
same position relative to the other items
NOTE:
Items are considered to be in the same relative order even if other items
are inserted or removed from the original order. For example, expanding
navigation menus may insert an additional level of detail or a secondary
navigation section may be inserted into the reading order.
Each item maintains its position relative to the other items. Items are considered to be in the same relative order even if other items are inserted or removed from the original order. For example, expanding navigation menus may insert an additional level of detail or a secondary navigation section may be inserted into the reading order.
translation of spoken words and other audible information into a language that uses a simultaneous combination of handshapes, facial expressions, and orientation and movement of the hands, arms or body to convey meaning.
Note: although some languages have a signed counterpart, most
sign languages are an independent language which is unrelated to the
spoken language of the same country or culture.
The way the parts of an authored unit are organized in relation to each other and;
The way a collection of delivery units is organized
The way the parts of an authored unit are organized in relation to each other and;
The way a collection of authored units is organized in relation to a delivery unit and;
The way a collection of delivery units is organized
Additional content that illustrates or clarifies default text content, which users may use instead of or in addition to the default text content.
For example, there may be supplements in text, graphics, and audio.
data format, programming or markup language, protocol or API
Technology means a data format, programming or markup language, protocol or API.
sequence of characters
NOTE:
Characters are those included in the Unicode/ISO/IEC
106464 repertoire.
programmatically determined text that is used in place of non-text content or text that is used in addition to non-text content and referred to from the programmatically determined text.
Content might be unfamiliar if you are using terms specific to a particular community. For example, many of the terms used in this document are specific to the disability community.
Unicode is a universal character set that defines all the characters needed for writing the majority of living languages in use on computers. For more information refer to the Unicode Consortium or to Tutorial: Character sets & encodings in XHTML, HTML and CSS produced by the W3C Internationalization Activity.
Note: Unicode The Unicode Consortium, The Unicode Standard,
Version 4.1.0, ISBN 0-321-18578-1, as updated from time to time by the
publication of new versions. (See http://www.unicode.org/unicode/standard/
versions for the latest version and additional information on versions
of the standard and of the Unicode Character Database).
a regular expression identifying a set of resources.
NOTE 1:
A
resource belongs to the set if the regular expression
matches its URI.
NOTE 2:
In order to be included in the set, the resource must
exist;
NOTE 3: The regular expression may, and typically will, match URIs that
do not refer to any existing resource.
used in such a way that users must know exactly what definition
to apply in order to understand the content correctly.
For example, the
word "representational" means something quite different if it occurs in a discussion of visual art as opposed to a treatise on government, but the appropriate definition can be determined from context. By contrast, the word "text" is used in a very specific way in WCAG 2.0, so a definition is supplied in the glossary.
Any software that retrieves and renders Web content for users.
EXAMPLES: Web browsers, media players, plug-ins, and other programs
— including assistive
technologies — that help in retrieving and rendering Web content.
changes in the visual appearance or sound of the text, such as changing to a different font or a different voice.
the technology of moving pictures or images.
NOTE: Video can be made up of animated or photographic images, or both
the technology of moving pictures or images. Video can be made up of animated or photographic images, or both.
a method developed at the University of Wisconsin - working
in conjunction with Dr. Graham Harding and Cambridge Research Associates
for applying the United Kingdom's "ITC
Guidance Note for Licensees on Flashing Images and Regular Patterns in
Television (Revised and re-issued July 2001)" to content displayed on a computer screen, such as Web pages and other computer
content.
NOTE:
The ITC Guidance Document is based on the assumption that the
television screen occupies the central ten degrees of vision. This is
not accurate for a screen which is located in front of a person. The
Wisconsin Algorithm basically carries out the same analysis as the ITC
Guidelines except that is does it on every possible ten degree window
for a prototypical computer display.
---- WAS - Wisconsin Computer Equivalence Algorithm
The Wisconsin Computer Equivalence Algorithm is a method for applying the United Kingdom's "ITC Guidance Note for Licensees on Flashing Images and Regular Patterns in Television (Revised and re-issued July 2001)" to content displayed on a computer screen, such as Web pages and other computer content. The ITC Guidance Document is based on the assumption that the television screen occupies the central ten degrees of vision. This is not accurate for a screen which is located in front of a person. The Wisconsin Algorithm basically carries out the same analysis as the ITC Guidelines except that is does it on every possible ten degree window for a prototypical computer display.