This document is an internal working draft published for review and
comment, specifically for several WAI working groups. It was
originally created by Harvey Bingham and is currently
being worked on as a proposed glossary for use in future versions of the
Authoring Tool Accessibility Guidelines [ATAG10], Techniques for Authoring Tool
Accessibility [ATAG10-TECH] User Agent
Accessibility Guidelines [UAAG10], Techniques for User Agent
Accessibility Guidelines [UAAG10-TECHS], XML Accessibility
Guidelines [XAG10],
as well as for Web Content Accessibility Guidelines 2.0 [WCAG20].
The purpose of this combined glossary is to allow comparison of
definitions, and potentially to provide a single glossary for all the
accessibility guidelines. The various WAI working groups and individual
readers of more than one guideline will benefit from a consistent use of
terms.
This is a draft document and may be updated, replaced, or obsoleted by
other documents at any time. It is inappropriate to use W3C Working Drafts as
reference material or to cite them as other than "work in progress". A list
of current W3C Recommendations and other technical
documents is available.
Publication of this document does not imply endorsement by the W3C, any of
its member organisations or working groups.
Translations of this document or of drafts may be available. Further
translations are welcome, but prospective translators should ensure that they
are familiar with W3C copyright and translation policy.
- A
- Access [WS-GLOSSARY] 2003-03-02
- To interact with a system entity in order to manipulate, use, gain
knowledge of, and/or obtain a representation of some or all of a system
entity's resources.
- Accessibility [WEAVING] GENERIC
- The art of ensuring that, to as large an extent as
possible, facilities (such as, for example, Web access) are available to people
whether or not they have impairments of one sort or another.
- Accessibility [ATAG10]
- See also: Accessible [ATAG10]
- Within these guidelines, "accessible Web content"
and "accessible authoring tool" mean that the content and tool can be
used by people regardless of disability.
- To understand the accessibility issues relevant to
authoring tool design, consider that many authors may be creating
content in contexts very different from your own:
- They may not be able to see, hear, move, or may not be able to
process some types of information easily or at all;
- They may have difficulty reading or comprehending text;
- They may not have or be able to use a keyboard or mouse;
- They may have a text-only display, or a small screen.
- Accessible design will benefit people in these
different authoring scenarios and also many people who do not have a
physical disability but who have similar needs.
Example: Someone may be working in a
noisy environment and thus require an alternative re of audio
information. Similarly, someone may be working in an eyes-busy
environment and thus require an audio equivalent to information they
cannot view. Users of small mobile devices (with small screens, no
keyboard, and no mouse) have similar functional needs as some users
with disabilities.
- Accessibility [HFES] 2001-11-13
- The set of properties that allows a product,
service, or facility to be used by people with a wide range of
capabilities, either directly or in conjunction with assistive
technologies. Although the term "accessibility" typically addresses
users who have a disability, the concept is not limited to disability
issues.
- Accessibility
Awareness [ATAG10] 2001-01-12
- An "accessibility-aware" application is one that has
been designed to account for authors' differing needs, abilities, and
technologies. In the case of authoring tools, this means that (1) care
has been taken to ensure that the content produced by user-authors is
accessible and (2) that the user interface has been designed to be
usable with a variety of display and control technologies.
- Accessibility
Information [ATAG10]
- "Accessibility information" is content, including
information and markup, that is used to improve the accessibility of a
document. Accessibility information includes, but is not limited to, equivalent alternative information.
- Accessibility
Permission [PDF-TECH] 2001-01-08
- A PDF file can be encrypted (PDF 1.1) to protect its
contents from unauthorized access. PDF's standard security handler
defines a set of access privileges for a document, including privileges
such as modifying the document's contents, copying text and graphics
from the document, and printing the document. In PDF 1.4, this set
includes accessibility permission, which controls whether the contents
of the document are available via standard accessibility APIs to screen
readers and other assistive technology.
- Accessibility
Problem [ATAG10] (Also: Inaccessible Markup
[ATAG10])
- See also: Inaccessible
Markup [ATAG10]
- Inaccessible Web content or authoring tools cannot
be used by some people with disabilities. The Web Content Accessibility
Guidelines 1.0 WCAG 1.0 describes how to create
accessible Web content.
- Accessible [WCAG10] [WCAG20] 2002-03-18 ISSUE
- Content is accessible when it may be used by someone
with a disability.
- Accessible [ATAG10]
- See Accessibility
[ATAG10].
- Accessible Authoring
Practice [ATAG10]
- "Accessible authoring practices" improve the
accessibility of Web content. Both authors and tools engage in
accessible authoring practices.
Example:, authors write clearly,
structure their content, and provide navigation aids. Tools
automatically generate valid markup and assist authors in providing and
managing appropriate equivalent alternatives.
- Access Key (s) [HFES] 2001-11-13
- See also Mnemonic, Modifier Key
- The portion of an option name or control label used
for keyboard selection. Also called mnemonic, implicit designator, or
menu mnemonic. See implicit designator.
- Acronym [WCAG10] [WCAG20] 2002-12-13
- An identifier formed from some of the letters (often
the initials) of a phrase and used as an abbreviation.
- Activate [UAAG10]
(Normative) 2003-03-01
- In this document, the verb "to activate" means
(depending on context) either:
The effect of activation depends on the type of enabled element or
user interface control. For instance, when a link is activated, the
user agent generally retrieves the linked Web resource. When a form control is
activated, it may change state (e.g., check boxes) or may take user
input (e.g., a text entry field).
- Active Element [SVG10] 2001-01-12
- An active element is an element with behaviors that
may be activated (or "triggered") either through the user interface or
through scripts. Which elements are active depends on the document
language and whether the features are supported by the user agent. In
SVG documents, for example active elements
include links and element instances with scripts (event handlers)
explicitly associated with them.
Example: Through the various "on"
attributes: onactivate etc. Most systems use the content focus to navigate active elements and
identify which is to be activated. An active element's behavior may be
triggered through any number of mechanisms, including the mouse,
keyboard, an Application Programming Interface (API), etc. The effect
of activation depends on the element. For instance, when a link is
activated, the user agent generally retrieves the linked resource.
- Active Element
[UAAG10]
- An active element is an element with behaviors that
may be activated (or
"triggered") either through the user interface or through an API (e.g., by using scripts). Some element
instances may be active at times but not at others (e.g., they may be
"deactivated" through scripts, or they are only active for a period of
time determined by the author). Which elements are active depends on
the document language and whether the features are supported by the
user agent. In HTML 4.01 HTML4.01 documents, for example, active elements include links, image
maps, form controls, element instances with a value for the "longdesc"
attribute, and element instances with scripts (event handlers)
explicitly associated with them (e.g., through the various "on"
attributes). Most systems use the content focus to navigate active
elements and identify which is to be activated. An active element's
behavior may be triggered through any number of mechanisms, including
the mouse, keyboard, an API, etc. The effect of
activation depends on the element. For instance, when a link is
activated, the user agent generally retrieves the linked web resources. When a form control is
activated, it may change state (e.g., check boxes) or may take user
input (e.g., a text field). Refer also to the definition of event handler
- Accessible design will benefit people in these
different authoring scenarios and also many people who do not have a
physical disability but who have similar needs.
Example: Someone may be working in a
noisy environment and thus require an alternative re of audio
information. Similarly, someone may be working in an eyes-busy
environment and thus require an audio equivalent to information they
cannot view. Users of small mobile devices (with small screens, no
keyboard, and no mouse) have similar functional needs as some users
with disabilities.
- Active Element
[UA Draft] 2001-02-03
- An active element is a piece of content with behaviors that may be activated
(or "triggered") either through the user interface or through an API (e.g., by using scripts).
What constitutes an active element depends on the content . In HTML 4
[HTML4] documents, for
example, active elements include links,
image maps, form controls, element instances with a value for the
"longdesc" attribute, and element instances with scripts (event
handlers) explicitly associated with them (e.g., through the various
"on" attributes). The requirements of this document refer only to
active elements that may be recognized through markup (and not, for
example, through scripts or style sheets).
Some element instances may be active at times but not at others (e.g.,
they may be "deactivated" through scripts, or they may only be active
for a period of time determined by the author).
Potential user interaction with a piece of content does not imply that the content
constitutes an active element.
Example: The user may select text an
copy it to the clipboard, but the selected text is not (necessarily) an
active element, because the selection is a functionality provided by
the user agent. For the purposes of this document, markup languages
determine which elements are potentially active elements.
The effect of activation depends on the element. For instance, when
a link is activated, the user agent generally retrieves the linked Web
resource. When a form control is activated, it may change
state (e.g., check boxes) or may take user input (e.g., a text entry
field). See also the definition of event
handler.
Most systems use the content
focus to indicate which active element will be activated on
user demand.
- ActualText Value [PDF-TECH]2001-01-08
- Sometimes characters are rendered by graphics
commands other than showstring. For instance, an illuminated character
may be rendered by an image or a series of graphics commands. In this
situations, the Actual Text property is used to identify the character
being rendered. This character may be concantentated with adjoining
text to form a word.
- Adobe Glyph
Name [PDF-TECH] 2001-01-11
- The name of a character in the Adobe standard
character encodings, in Appendix D of the PDF 1.3 Reference Manual. The
encodings list characters, character names, and character codes used in
platform standard encodings.
- Afford, Affordance [HFES] 2001-04-13 Human Factors &
HCI, Al Gilman
- An affordance is an effective service delivery; one
that makes it into user space where the user can actually use it. Or
the effect of the service delivery as observed within user space.
- Aging-Related
Conditions [PWD-Use-Web] 2001-03-18
- Changes in people's functional ability due to aging
can include subtle and/or gradual changes in abilities or a combination
of abilities including vision, hearing, dexterity and memory. Any one
of these limitations can affect an individual's ability to access Web
content.
- Alert [ATAG10] 2001-01-12
- An "alert" draws the author's attention to an event
or situation. It may require a response from the author. An alert warns
the author that there are problems that need to be addressed.
Attracting the author's attention artfully can be challenging, since
author perceptions of alerts, prompts, and warnings can influence
opinions of the tool and even of accessible authoring.
An Unintrusive Alert is an alert such as an icon,
underlining, or gentle sound that can be presented to the author
without necessitating immediate action.
Example: In some word processors
misspelled text is highlighted without forcing the author to make
immediate corrections. These alerts allow authors to continue editing
with the knowledge that problems will be easy to identify at a later
time. However, authors may become annoyed at the extra formatting or
may choose to ignore the alerts altogether.
An Interruptive Alert is an informative message that
interrupts the editing process for the author.
Example: Interruptive alerts are often
presented when an author's action could cause a loss of data.
Interruptive alerts allow problems to be brought to the author's
attention immediately. However, authors may resent the constant delays
and forced actions. Many people prefer to finish expressing an idea
before returning to edit its format.
- Alert [UAAG10]
(Normative) 2003-03-01
- To "alert" means to make the user aware of some
event, without requiring acknowledgement.
Example: The user agent may alert the
user that new content is
available on the server by displaying a text message in the user
agent's status bar.
- Alternative Equivalents for
Content [UAAG10] 2001-02-03
- Since rendered content in some
forms is not always accessible to users with disabilities, authors must
supply alternative equivalents for content. In the context of this
document, the equivalent must fulfill essentially the same function for
the person with a disability (at least insofar as is feasible, given
the nature of the disability and the state of technology), as the
"primary" content does for
the person without any disability.
Example: The text "The Full Moon" might
convey the same information as an image of a full moon when presented
to users.
Note: That equivalent information focuses
on fulfilling the same function. If the image is part of a link and
understanding the image is crucial to guessing the link target, an
equivalent must also give users an idea of the link target. User agents
must make the alternative equivalent content available to users or software that
require it (in place of and/or in addition to the "primary" content).
Alternative representations include text equivalents (long and short,
synchronized and unsynchronized) and non-text equivalents (e.g.,
captions, auditory descriptions, a visual track that shows sign
language translation of a written text, etc.).
- Alternative Information
[ATAG10]
- (Also: Equivalent Alternative
[ATAG10] & Text equivalent
WC)
- Content is "equivalent" to other content when both fulfill essentially the same
function or purpose upon presentation
to the user. Equivalent alternatives play an important role in
accessible authoring practices since certain types of content may not
be accessible to all users (e.g., video, images, audio, etc.). Authors
are encouraged to provide text equivalents for non-text content since
text may be rendered as synthesized speech for individuals who have
visual or learning disabilities, as braille for individuals who are
blind, or as graphical text for individuals who are deaf or do not have
a disability. For more information about equivalent alternatives,
please refer to the Web Content Accessibility Guidelines WCAG 1.0 WCAG 1.0.
- Alternative Keyboards or
Switches [PWD-Use-Web] 2001-03-18
- Alternate keyboards or switches are hardware or
software devices used by people with physical disabilities, that
provide an alternate way of creating keystrokes that appear to come
from the standard keyboard.
Examples: Include keyboard with
extra-small or extra-large key spacing, keyguards that only allow
pressing one key at a time, on-screen keyboards, eyegaze keyboards, and
sip-and-puff switches. Web-based applications that can be operated
entirely from the keyboard, with no mouse required, support a wide
range of alternative modes of input.
- Animation [WCAG10-TECH] 2001-03-10
- In this document, the term "animation" refers to any
visual movement effect created automatically (i.e., without manual user
interaction). This definition of animation includes video and animated
images. Animation techniques include:
- graphically displaying a sequence of snapshots within the same
region (e.g., as is done for video and animated images). The series
of snapshots may be provided by a single resource (e.g., an
animated GIF image) or from distinct resources (e.g., a series of
images downloaded continuously by the user agent).
- scrolling text (e.g., achieved through markup or style
sheets).
- displacing graphical objects around the viewport (e.g., a picture
of a ball that is moved around the viewport giving the impression
that it is bouncing off of the viewport edges). For instance, the
SMIL 2.0 [SMIL20] animation modules explain how to create such
animation effects in a declarative manner (i.e., not by composition
of successive snapshots).
- Animation [UAAG10]
(Normative) 2003-01-03
- In this document, an "animation" refers to content that, when rendered, creates a visual
movement effect automatically (i.e., without manual user interaction).
This definition of animation includes video and animated images.
Animation techniques include:
- graphically displaying a sequence of snapshots within the same
region (e.g., as is done for video and animated images). The series
of snapshots may be provided by a single resource (e.g., an
animated GIF image) or from distinct resources (e.g., a series of
images downloaded continuously by the user agent).
- scrolling text (e.g., achieved through markup or style
sheets).
- displacing graphical objects around the viewport (e.g., a picture
of a ball that is moved around the viewport giving the impression
that it is bouncing off of the viewport edges). For instance, the
SMIL 2.0 [SMIL20] animation modules explain how to create such
animation effects in a declarative manner (i.e., not by composition
of successive snapshots).
- Anonymity [WS-GLOSSARY] 2003-03-02
- The quality or state of being anonymous, which is the condition of
having a name or identity that is unknown or concealed.
- Annotation 2001-05-07 Annotation
Glossary
- A Web object (i.e. an object with a URI) about which
there exist some [RDF] statements using an annotation vocabulary. The
annotation vocabulary will typically describe a relationship between
the annotation and one or more other Web resources to which the
annotation is attached.
- Annotation
Service 2001-05-07 Annotation Glossary
- A URI for an HTTP service that supports reading and
writing of chunks of RDF. A single HTTP server (e.g.
http://www.w3.org:80/) may support multiple annotation servers, each
with its own branch of the URI space; e.g.
http://www.w3.org/Team/Annotation/ is logically a distinct annotation
service from http://www.w3.org/Member/Annotation/.
- Annotea 2001-05-07 Annotation
Glossary
- @@
- Anonymization [CC-PP] 2001-04-23
- Hiding the identity of the User as a security
precaution.
- Applet [WCAG10] [WCAG20] 2001-01-11
- A Java program inserted into a Web page that relies
on a browser to provide the environment in which it can run. Applets
are essentially guests of the browser. The browser takes care of their
welfare and provides and manages access to the platform specific
services.
- Applet [UAAG10] (Normative) 2003-01-03
- An applet is a program (generally written in the
Java programming language) that is part of content, and that the user agent
executes.
- Application Programming Interface (API),
conventional input / output device [UAAG10]
(Normative) 2003-03-01
- An application programming interface (API) defines how
communication may take place between applications.
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.
Example: The conventional input APIs of
the target 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.
- API's [WCAG10] [WCAG20] 2001-01-11
- An application programming interface (API) defines how
communication may take place between applications.
- A device API defines how
communication may take place with an input or output device such as a
keyboard, mouse, video card, etc.
- A standard device API is one that
is considered standard for that particular device on a given operating
or windowing system.
- Appropriate [ATAG10] 2002-02-27 ISSUE
- @@
- Array [WCAG10] [WCAG20]
- A set of elements of some type that can be
identified by an index, starting in JavaScript at 0, and increasing by
1 for each subsequent member of the array.
- Assistive
Technology 2001-12-29 [Access Board]
- Any item, piece of equipment, or system, whether
acquired commercially, modified, or customized, that is commonly used
to increase, maintain, or improve functional capabilities of
individuals with disabilities.
[36 C.F.R. 1194.4]
- Assistive
Technology [UAAG10]
(Normative) 2003-03-01
- In the context of this document, an assistive
technology is a user agent that:
- relies on services (such as retrieving Web resources 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.
- 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).
Examples of assistive technologies
that are important in the context of this document include the
following:
- screen magnifiers, which are used by people with visual
disabilities to enlarge and change colors on the screen to
improve the visual readability of rendered text and images.
- screen readers, which are used by people who are blind or
have reading disabilities to read textual information through
synthesized speech or braille displays.
- voice recognition software, which may be used by people who
have some physical disabilities.
- alternative keyboards, which are used by people with certain
physical disabilities to simulate the keyboard.
- alternative pointing devices, which are used by people with
certain physical disabilities to simulate mouse pointing and
button activations.
- Beyond this document, assistive technologies consist
of software or hardware that has been specifically designed to assist
people with disabilities in carrying out daily activities. These
technologies include wheelchairs, reading machines, devices for
grasping, text telephones, and vibrating pagers. For example, the
following very general definition of "assistive technology device"
comes from the (U.S.) Assistive Technology Act of 1998 [AT1998]:
Any item, piece of equipment, or product system, whether acquired
commercially, modified, or customized, that is used to increase,
maintain, or improve functional capabilities of individuals with
disabilities.
- Assistive Technology Devices
(Visual Disabilities) 2001-10-12 RNIB Devices for
blind and the partially sighted. Glossary
- Web Browsers for Non-Visual Output
- @@
- @@
- @@
- @@
- @@
- @@
- @@
- @@
- @@
- @@
- @@
- Attention Deficit Disorder, or
ADD [@@] (Normative) 2003-03-01
- @@
- Attribute [ATAG10-TECHS] [ATAG-Wombat] 2001-08-25
This document uses the term "attribute" as used
in SGML and XML ([XML]) : Element types may be defined
as having any number of attributes. Some attributes are integral to the
accessibility of content (e.g.,
the "alt", "title", and
"longdesc" attributes in HTML).
Example: Below, the attributes of the
beverage element type are "flavour", which
has the value "lots", and "colour", which has the value
"red": <beverage flavour="lots" colour="red">my
favourite</beverage>
- Attribute [UAAG10]
(Normative) 2003-03-01
- This document uses the term "attribute" in the XML
sense: an element may have a set of attribute specifications (refer to
the XML 1.0 specification [XML] section 3).
- Attribute [WS-GLOSSARY] 2003-03-02
- A distinct characteristic of an object. An object's attributes are
said to describe the object. Objects' attributes are often specified in
terms of their physical traits, such as size, shape, weight, and color,
etc., for real-world objects. Objects in cyberspace might have
attributes describing size, type of encoding, network address, etc.
Salient attributes of an object is decided by the beholder.
- Audio [UAAG10]
(Normative) 2003-03-01
- In this document, the term "audio" refers to content that encodes prerecorded sound.
- Audio-only
presentation [UAAG10] (Normative)
2003-03-01
- An audio-only presentation is content consisting exclusively of one or more
audio tracks presented
concurrently or in series. Examples of an audio-only presentation
include a musical performance, a radio-style news broadcast, and a
narration.
- Audio track [UAAG10]
(Normative) 2003-03-01
- An audio object is content rendered as sound through
an audio viewport. An audio track is an
audio object that is intended as a whole or partial presentation. An
audio track may, but is not required to, correspond to a single audio
channel (left or right audio channel).
- Audio Description, Auditory
Description [UAAG10] 2003-03-01
- An audio description (called an "auditory
description" in the Web Content Accessibility Guidelines 1.0 [WCAG10]) is either a
prerecorded human voice or a synthesized voice (recorded or generated
dynamically) describing the key visual elements of a movie or other
animation. The audio description is synchronized with (and possibly
included as part of) the audio track of the presentation,
usually during natural pauses in the audio track. Audio descriptions
include information about actions, body language, graphics, and scene
changes.
- Audio
Descriptions [WCAG20] 2003-03-02
- @@
- Authentication [WS-GLOSSARY] 2003-03-02
- To positively verify the identity of a user, device, or other entity
in a computer system, often as a prerequisite to allowing access to
resources in a system.
- Authentication
Code 2001-05-07 XML-Signature Syntax and Processing
- A value generated from the application of a shared
key to a message via a cryptographic algorithm such that it has the
properties of message authentication (integrity) but not signer
authentication.
- Authoring Tool [ATAG10-TECHS] [ATAG-Wombat] 2001-08-25
- An "authoring tool" is any software that is used to
produce content for
publishing on the Web. Authoring tools include:
- Markup Editing Tools
Editing tools specifically designed to produce Web content (e.g.,
WYSIWYG, HTML and XML editors)
- Multimedia Creation Tools
Tools that produce multimedia, especially where it is intended for
use on the Web (e.g., video production and editing suites, SMIL
authoring packages)
- Content Management Tools
Tools for site management or site publication, including tools that
automatically generate Web sites dynamically from a database,
on-the-fly conversion and Web site publishing tools
- Programming Tools
Tools that offer the option of saving material in a Web format
(e.g., word processors, spread-sheet or desktop publishing
packages)
- Layout Management Tools
Tools for management of layout (e.g., CSS, [XSLT10] and JSS formatting
tools)
- Transformation Filtering Tools
Tools for management of layout (e. Tools that transform documents
into Web formats (e.g., filters to transform desktop publishing
formats to HTML)
- Author styles [UAAG10]
(Normative) 2003-03-01
- Authors styles are style property
values that come from content (e.g., style
sheets within a document, that are associated with a document, or that
are generated by a server).
- Authorization [WS-GLOSSARY] 2003-03-02
- The process of determining, by evaluating applicable access control
information, whether a subject is allowed to have the specified types
of access to a particular resource. Usually, authorization is in the
context of authentication. Once a subject is authenticated, it may be
authorized to perform different types of access.
- Automated Markup Insertion
Function [ATAG10-TECHS] [ATAG-Wombat] 2001-08-25
- "Automated markup insertion functions" are the
features of an authoring tool that allow the author to produce markup
without directly typing it. This includes a wide range of tools from
simple markup insertion aids (such as a bold button on a toolbar) to
markup managers (such as table makers that include powerful tools such
as "split cells" that can make multiple changes) to high level site
building wizards that produce almost complete documents on the basis of
a series of author preferences.
- Avatar 2002-02-24 IMS Guidelines for
Developing Accessible Learning Applications and iCan
- See also Signing Avatar
- Avatars are realistically animated, on-screen,
interactive human characters. A particular use of Avatars for
accessibility is to create signing Avatars.
- Available [ATAG10] 2002-02-27 ISSUE
- @@
- B
- Backward
Compatible [WCAG10] [WCAG20]
- Design that continues to work with earlier versions
of a language, program, etc.
- Basic Shape [SVG10] 2001-02-02
- Standard shapes which are predefined in SVG as a
convenience for common graphical operations. Specifically: 'rect',
'circle', 'ellipse', 'line', 'polyline', 'polygon'.
- Binding [XFORMS10]
NEW 2001-07-15
- The connection between a form control and a model
item and an instance data item, represented as a binding expression.
- Binding [WS-GLOSSARY] 2003-03-02
- An association between an Interface, a concrete protocol and a data
format. A Binding specifies the protocol and data format to be used in
transmitting messages defined by the associated Interface.
- Binding
Expression [XFORMS10] 2001-07-15
- An XPath addressing expression used by the binding
to connect form controls to other parts of XForms.
- Blindness [PWD-Use-Web] 2001-03-19
- Blindness involves a substantial, uncorrectable loss
of vision in both eyes.
- Boolean [WCAG10] [WCAG20] 2001-05-07
- A primitive data type that only can have values of
true or false. As in radio buttons. Also, a variable of Boolean type or
a function with Boolean arguments or result. The most common Boolean
functions are AND, OR and NOT.
- Braille [WCAG10] [WCAG20] 2001-01-26
- Braille uses six raised dots in different patterns
to represent letters and numbers to be read by people who are blind
with their fingertips. An image of the word "Accessible" in braille
follows:
- A braille
display, commonly referred to as a "dynamic braille
display," raises or lowers dot patterns on command from an electronic
device, usually a computer. The result is a line of braille that can
change from moment to moment. Current dynamic braille displays range in
size from one cell (six or eight dots) to an eighty-cell line, most
having between twelve and twenty cells per line.
- Braille and Refreshable
Braille [PWD-Use-Web] 2001-03-18
- Braille is a system using six to eight raised dots
in various patterns to represent letters and numbers that can be read
by the fingertips. Braille systems vary greatly around the world. Some
"grades" of braille include additional codes beyond standard
alpha-numeric characters to represent common letter groupings (e.g.,
"th," "ble" in Grade II American English braille) in order to make
braille more compact. An 8-dot version of braille has been developed to
allow all ASCII characters to be represented. Dynamic or refreshable
braille involves the use of a mechanical display where dots (pins) can
be raised and lowered dynamically to allow any braille characters to be
displayed.
- Browser (for Non-Visual
Output) 2001-10-12 RNIB Devices for blind and the partially sighted.
Glossary
- See also Web
Browsers, Voice
Browsers
- Blind and partially sighted people will use one of
three possible methods to read pages on the World Wide Web. Users with
some sight can use screen magnification software. For users with little
or no useful sight the options are Speech
Synthesizers or sound card to convert text into speech or a
refreshable braille display to convert text into braille.
- eReader - CAST
- @@
- Browser [WS-GLOSSARY] 2003-03-02
- A system entity that is used by an end user to access a Web site. A
browser provides a run-time environment for distributed application
components on the client's device.
- C
- Cache [CC-PP] 2001-04-23
- A storage area used by a server or proxy to store
data resources that have been retrieved or created in response to a
request. When a new request for a "cached" data resource is received,
the server or proxy can respond with the cached version instead of
retrieving or creating a new copy.
- Cacheable [CC-PP] 2001-04-23
- A data resource is said to be "cacheable" if the
data resource contains a property that allows a sever to determine
whether the cached resource matches a request for a similar
resource.
- Canvas [SVG10] 2001-02-02
- A surface onto which graphics elements are drawn,
which can be real physical media such as a display or paper or an
abstract surface such as a allocated region of computer memory.
- Captions [ATAG10]
- "Captions" are essential text
equivalents for movie audio. Captions consist of a text
transcript of the auditory track of the movie (or other
video presentation) that is
synchronized with the video and auditory tracks. Captions are generally
rendered graphically and benefit people who can see but are deaf,
hard-of-hearing, or cannot hear the audio.
- Captions [UAAG10]
(Normative) 2003-03-01
- Captions are text transcripts that are synchronized with other audio tracks or visual tracks. Captions convey
information about spoken words and non-spoken sounds such as sound
effects. They benefit people who are deaf or hard-of-hearing, and
anyone who cannot hear the audio (e.g., someone in a noisy
environment). Captions are generally rendered graphically superimposed ("on top
of") the synchronized visual track.
The term "open captions" generally refers to captions that are
always rendered with a visual track; they cannot be turned off. The
term "closed captions" generally refers to captions that may be turned
on and off. The captions requirements of this document assume that the
user agent can recognize the
captions as such; see the section on applicability for more
information.
Note: Other terms that include the word
"caption" may have different meanings in this document. For instance, a
"table caption" is a title for the table, often positioned graphically
above or below the table. In this document, the intended meaning of
"caption" will be clear from context.
- Captions [WCAG20] 2003-03-02
- @@
- Capability [CC-PP] 2001-04-23
- An attribute of a sender or receiver (often the
receiver) which indicates an ability to generate or process a
particular type of message content .
- Cascading Style Sheet
(s) [High-Tech] 2001-12-29
- See also [XSLT10]
- Style sheets describe how documents are presented on
screens, in print, and even in spoken voice. Style sheets allow the
user to change the appearance of hundreds of Web pages by changing just
one file. A style sheet is made up of rules that tell a browser how to
present a document. Numerous properties may be defined for an element;
each property is given a value.
- CC-PP [CC-PP] 2001-04-23
- Composite Capability/Preference Profiles.
A CC-PP profile is a description of device capabilities and user
preferences that can be used to guide the adaptation of content presented to that device.
As the number and variety of devices connected to the Internet grows,
there is a corresponding increase in the need to deliver content that
is tailored to the capabilities of different devices. Some limited
techniques, such as HTTP accept headers and HTML alt tags, already
exist. As part of a framework for content adaptation and
contextualization, a general purpose profile format is required that
can describe the capabilities of a user agent and preferences of its
user. CC-PP is designed to be such a format.
- CC-PP
Repository [CC-PP] 2001-04-23
- A server that stores the User Agent Profile or
profile segments persistently in a form that may be referenced by and
incorporated into a profile. A CC-PP repository is typically a Web
server that provides CC-PP profiles or profile segments in response to
HTTP requests.
- Channel
Security [CC-PP] 2001-04-23
- A form of security (authentication and/or
confidentiality) that operates on a given communication channel,
regardless of the information that is transferred over that channel.
The security thus provided is between the end-points of the channel
only.
- Character [P3P] 2001-02-27
- Strings consist of a sequence of zero or more
characters, where a character is defined as in the XML Recommendation
[XML]. A single character in P3P thus corresponds to a single Unicode
abstract character with a single corresponding Unicode scalar value
(see [UNICODE]).
- Characters [PDF-TECH]
2000-12-14
- A character is a printable symbol having phonetic or
pictographic meaning and usually forming part of a word of text,
depicting a numeral, or expressing grammatical punctuation. A character
is generally one of a limited number of symbols, including the letters
of a particular language's alphabet, the numerals in the decimal number
system, and certain special symbols such as the ampersand and "atsign"
@. Several standards of computer encoding have been developed for
characters. The most commonly used in personal computers is ASCII. IBM
mainframe systems use extended binary-coded decimal interchange code. A
new standard, Unicode, is supported by the
Windows NT system. A distinction is sometimes made between a character
and a glyph. In this distinction, a character can be distinguished from
other characters in terms of meaning and sound and a glyph is the graphic image used to portray the
character. In different implementations, a character can have more than
one possible glyph, and a glyph can represent more than one possible
character.
- Character Codes
[PDF-TECH]
2002-12-13
- (a la Loretta)A show string is the encoded re of a
sequence of non-negative integers. Each of those integers is a
Character Code. The interpretation of a show string depends on the
associated font: some fonts imply a one-byte re whie others imply a
more complicated re.
A mapping from a set of integers to a set of characters. This mapping
is generally 1:1 (i.e., bijective), for example, the code position 65 in ASCII maps only
to "A", and it's the only position that maps to "A". There are several
standard coded character sets, the most widely used is ASCII, generally
in its Latin-1 dialect (the ASCII coded character set, encoded directly
as single-byte values), or UTF-8 (the Unicode coded character set,
encoded with an 8-bit transformation method), with Unicode becoming
slowly more common; while EBCDIC and Baudot are extinct except in
legacy systems. A coded character set may include letters, digits,
punctuation, control codes, various mathematical and typographic
symbols, and other characters. Each character in the set is represented
by a unique character code (or "code position").
- Character
Encoding [UAAG10]
(Normative) 2003-03-01
- A "character encoding" is a mapping from a character
set definition to the actual code units used to represent the data.
Please refer to the Unicode specification [UNICODE] for more
information about character encodings. Refer to "Character Model for
the World Wide Web" [CHARMOD] for additional
information about characters and character encodings.
- Character Input
[WCAG20] 2003-03-02
- @@
- Check for [ATAG10]
- As used in checkpoint
4.1, "check for" can refer to three types of checking:
- In some instances, an authoring tool will be able to check for
accessibility problems automatically.
Example: Checking for validity ( checkpoint 2.2) or
testing whether an image is the only content of a link.
- In some cases, the tool will be able to "suspect" or "guess" that
there is a problem, but will need confirmation from the author.
Example: In making sure that a
sensible reading order is preserved a tool can present a linearized
version of a page to the author.
- In some cases, a tool must rely mostly on the author, and can
only ask the author to check.
Example: The tool may prompt the
author to verify that equivalent alternatives for multimedia are
appropriate. This is the minimal standard to be satisfied. Subtle,
rather than extensive, prompting is more likely to be effective in
encouraging the author to verify accessibility where it cannot be
done automatically.
- Class [WCAG10] [WCAG20]
- A Beginning...01-01-25 A
description or template of an object that describes the
responsibilities, the operations, and the state, which can then be used
to create instancess.
Example: A Car class, which could be
used as the template for instances of a class such as myGreyHonda or
yourPurpleBeetle.
- Client 2001-05-07Generic - Dept of
Computing Imperial College of Science, Technology and Medicine
http://www.doc.ic.ac.uk/
- A computer system or process that requests a service
of another computer system or process (a "server") using some kind of
protocol and accepts the server's responses. A client is part of a
client-server software architecture.
Example: A workstation requesting the
contents of a file from a file server is a client of the file
server.
- Client [CC-PP] 2001-04-23
- An entity that is the original compositor of a CC-PP
profile.
- Client-side
Scripting [WCAG20] [Script Techniques] 2002-03-17 NCI National Cancer
Institute
- See also Scripting
- Web programming that sends instructions for actions
to be performed on the client, or user's, computer, such as changing
the appearance of a page in the user's browser. In order to display the
page or change as intended, the user's system must be able to recognize
and process the programming.
- Clipping Path [SVG10] 2001-02-02
- Is a combination of 'path', 'text' and basic shapes
which serve as the outline of a (in the absense of antialiasing) 1-bit
mask, where everything on the "inside" of the outline is allowed to
show through but everything on the outside is masked out. See Clipping
paths.
- CMap [PDF-TECH]
2001-01-08
- A CMap specifies the mapping from character codes to
character selectors (CIDs, character names, or character codes) in one
or more associated fonts or CIDFonts. It serves a function analogous to
the Encoding dictionary for a simple font. A Cmap also specifies the
writing mode - horizontal or vertical - for any CIDFont with which the
CMap is combined.
Also a CMap (character map) file specifies the correspondence between
character codes and the CID (character identifier) numbers used to
identify characters. For composite (Type 0) fonts, it is the equivalent
to the concept of an encoding in a simple font. A CMap can describe a
mapping from multiple-byte codes to thousands of characters in a large
CID-keyed font.
- Cognitive and Neurological
Disabilities [PWD-Use-Web] 2001-03-19
- Dyslexia,
Dyscalculia
- Attention Deficit Disorder, or ADD
- Attention Deficit Hyperactive Disorder, or ADHD
- Impairments of Intelligence, or Learning Disabilities
- Memory Impairments
- Mental Health Disabilities
- Seizure Disorders
- Collated Text
Transcript [UAAG10] (Normative)
2003-03-01
- A collated text transcript is a text
equivalents of a movie or animation. More specifically, it
is the combination of the text
transcript of the audio track and the text equivalent of the
visual track.
Example: A collated text transcript
typically includes segments of spoken dialogue interspersed with text
descriptions of the key visual elements of a presentation (actions,
body language, graphics, and scene changes). See also the definitions
of text transcript and audio description. Collated
text transcripts are essential for individuals who are deaf-blind.
- Color Blindness
[PWD-Use-Web] 2001-03-19
- Color blindness is a lack of sensitivity to certain
colors. Common forms of color blindness include difficulty
distinguishing between red and green, or between yellow and blue.
Sometimes color blindness results in the inability to perceive any
color.
- Column Headers [PDF-TECH]
ISSUE
- @@
- Competitive
Activity [WCAG20] 2003-03-02
- @@
- Complex [WCAG20] 2003-03-02
- @@
- Component [WS-GLOSSARY] 2003-03-02
- A component is a software object, meant to interact with other
components, encapsulating certain functionality or a set of
functionalities. A component has a clearly defined interface and
conforms to a prescribed behavior common to all components within
an architecture.
- A component is an abstract unit of software instructions and
internal state that provides a transformation of data via its
interface.
- Computed
Expression [XFORMS10] 2001-07-15
- An XPath expression used by model item properties
such as relevant and calculate to include dynamic functionality in
XForms.
- Concatenate [PDF-TECH]
2002-12-13
- To combine character strings, to join together two
or more files or lists to form one big one.
Example: The Unix cat command can be
used to concatenate files.
- Concatenation [WCAG10] [WCAG20] 2001-01-25
- The operation of constructing a large string from
two smaller strings. The result of a concatenation will have all the
contents of both smaller strings.
- Conditional-content
[UAAG10]
(Normative) 2003-03-01
- Conditional content is content that, by format
specification, should be made available to users through the user
interface, generally under certain conditions (e.g., user preferences
or operating environment limitations). Some examples of conditional content mechanisms
include:
- The "
alt" attribute of the IMG element
in HTML 4. According to section
13.2 of the HTML 4 specification ([HTML4]): "User agents
must render alternate text when they cannot support images, they
cannot support a certain image type or when they are configured not
to display images."
OBJECT elements in HTML 4. Section
13.3.1 of the HTML 4 specification ([HTML4]) explains the
conditional rendering rules of (nested) OBJECT
elements.- The
switch element and test attributes in SMIL 1.0.
Sections 4.3
and 4.4,
respectively, of SMIL 1.0 [SMIL] explain the
conditional rendering rules of these features.
- SVG 1.0 [SVG] also includes a
switch element and several attributes for conditional
processing.
- The
NOSCRIPT and NOFRAMES elements in
HTML 4 [HTML4] allow the author
to provide content
under conditions when the user agent does not support scripts or
frames, or the user has turned off support for scripts or frames.
Specifications vary in how completely they define how and when to
render conditional content. For instance, the HTML 4 specification
includes the rendering conditions for the "alt" attribute,
but not for the "title" attribute. The HTML 4
specification does indicate that the "title" attribute
should be available to users through the user interface ("Values of the
title attribute may be rendered by user agents in a variety of
ways...").
Note: The Web Content Accessibility
Guidelines 1.0 requires that authors provide text equivalents for
non-text content. This is generally done by using the conditional
content mechanisms of a markup language. Since conditional content may
not be rendered by default, the current document requires the user
agent to provide access to unrendered conditional content (checkpoints
2.3 and 2.9) as it may have been provided to promote
accessibility.
- Configure
and Control [UAAG10] (Normative)
2003-03-01
In the context of this [UA] document, the verbs
"to control" and "to configure" share in common the idea of governance
such as a user may exercise over interface layout, user agent behavior, rendering style, and
other parameters required by this [UA] document. Generally, the
difference in the terms centers on the idea of persistence.
When a user makes a change by "controlling" a setting, that change
usually does not persist beyond that user session. On the other hand,
when a user "configures" a setting, that setting typically persists
into later user sessions. Furthermore, the term "control" typically
means that the change can be made easily (such as through a keyboard
shortcut) and that the results of the change occur immediately. The
term "configure" typically means that making the change requires more
time and effort (such as making the change via a series of menus
leading to a dialog box, via style sheets or scripts). The results of
"configuration" might not take effect immediately (e.g., due to time
spent reinitializing the system, initiating a new session, or rebooting
the system).
In order to be able to configure and control the
user agent, the user needs to be able to "write" as well as "read"
values for these parameters. Configuration settings may be stored in a
profile. The range and granularity of
the changes that can be controlled or configured by the user may depend
on limitations of the operating environment
or hardware.
Both configuration and control may apply at different "levels":
across Web resources (i.e., at the user
agent level, or inherited from the operating environment), to the entirety
of a Web resource, or to components of a Web resource (e.g., on a
per-element basis).
A global
configuration is one that applies across elements of
the same Web resource, as well as across Web resources.
User agents may allow users to choose configurations based on
various parameters, such as hardware capabilities or natural language
preferences.
Note: In this document, the noun "control"
refers to a user
interface control.
- Conformance [WCAG10] [WCAG20] 2001-01-11 ISSUE
- @@
- Container
Element [SVG10] 2001-02-02
- An element which can have graphics elements and
other container elements as child elements. Specifically: 'svg', 'g',
'defs' 'symbol', 'clipPath', 'mask', 'pattern', 'marker', 'a' and
'switch'.
- Containing
Document [XFORMS10] 2001-07-15
- A specific document, for example an XHTML document, in which one or more
xform elements are found.
- Content [ATAG10]
- In this specification, the term "content " is used in two ways:
- Content refers to the document object as a whole or in
parts. Phrases such as "content type", "text content", and
"language of content" refer to this usage. When used in this sense,
the term content encompasses equivalent alternatives. Refer also
to the definition of rendered content. and other
accessibility information.
- Content refers to the content of an HTML or XML element, in the
sense employed by the XML 1.0 specification ( XML, section 3.1): "The text
between the start-tag and end-tag is called the element's content."
Context should indicate that the term content is being used in this
sense.
- Content [UAAG10]
(Normative) 2003-03-01
- In this specification, the noun "content" is used in
three ways:
- It is used to mean the document object as a
whole or in parts.
- It is used to mean the content of an HTML or XML element, in the
sense employed by the XML 1.0 specification ([XML],
section 3.1): "The text between the start-tag and end-tag is called
the element's content." Context should indicate that the term
content is being used in this sense.
- It is used in the terms non-text content and text content.
Empty content
(which may be conditional
content) is either a null value or an empty string (i.e., one that
is zero characters long). For instance, in HTML, alt=""
sets the value of the "alt" attribute to the empty string.
In some markup languages, an element may have empty content (e.g., the
HR element in HTML).
- Content [WCAG20] 2003-03-02
- @@
- Content
Generation [CC-PP] 2003-03-05
- For the purpose of this specification, "content
generation" refers to generating content appropriate to the user agent
profile of the request by using the user agent profile as input to a
dynamic content generation engine. The XSL and style sheets of the
document are used to tailor the document to the user agent profile of
the request
- Content Model
[DOM2] 2001-03-10
- The content model is a simple grammar governing the
allowed types of the child elements and the order in which they appear.
See Element Content in XML [XML].
- Content
Negotiation [CC-PP] 2001-03-10
- The mechanism for selecting the appropriate
representation when servicing a request. The representation of entities
in any response can be negotiated (including error responses).
- Content
Selection [CC-PP] 2003-03-05
- For the purpose of this specification, "content
selection" refers to selecting an appropriate document from a list of
possible choices or variants by matching the document profile with the
user agent profile of the request.
- Content
Provider [CC-PP] 2003-03-05
- A server that originates content in response to a
request.
- Context [DOM2] 2001-03-10
- A context specifies an access pattern (or path): a
set of interfaces which give you a way to interact with a model.
Example: Imagine a model with different
colored arcs connecting data nodes. A context might be a sheet of
colored acetate that is placed over the model allowing you a partial
view of the total information in the model.
- Contrast [HFES] 2001-11-13
- A difference in visual attributes (e.g., hue,
lightness, saturation) of an object's foreground and background.
- Control [UAAG10]
- See Configure UA
- Conventional input / output
device [UAAG10]
(Normative) 2002-10-28
- See Application
Programming Interface (API) UA
- Conversion Tool
[ATAG10]
- A "conversion tool" is any application or
application feature (e.g., "Save as HTML") that transforms convent in
one format to another format (such as a markup language).
- Cookie 2001-03-24 Web Characterization
Terminology & Definitions Sheet
- Data sent by a Web server to a Web client, to be
stored locally by the client and sent back to the server on subsequent
requests.
- Country Code [RFC2828] 2001-03-11
- An identifier that is defined for a nation by ISO.
For each nation, ISO Standard 3166 defines a unique two- character
alphabetic code, a unique three-character alphabetic code, and a
three-digit code. Among many uses of these codes, the two-character
codes are used as top-level domain names.
- Crop Box [PDF-TECH]
2001-01-08
- The crop box defines the region to which the
contents of the page are to be clipped (cropped) when displayed or
printed.
- CTM [SVG10]
- See Current
Transformation Matrix SVG
- Current Innermost SVG
Document Target [SVG10] 2001-02-02
- The XML document sub-tree which starts with the most
immediate ancestor 'svg' element of a given SVG element.
- Current SVG Document
Fragment [SVG10] 2001-02-02
- The XML document sub-tree which starts with the
outermost ancestor 'svg' element of a given SVG element, with the
requirement that all container elements between the outermost 'svg' and
this element are all elements in the SVG language.
- Current
Selection [UAAG10]
- See Selection UA
- Current Transformation Matrix
(CTM) [SVG10] 2001-02-02
- Transformation matrices define the mathematical
mapping from one coordinate system into another using a 3x3 matrix
using the equation [x' y' 1] = [x y 1] * matrix. The current
transformation matrix (CTM) defines the mapping from the user
coordinate system into the viewport coordinate system.
- Current User
Selection [ATAG10-TECHS] [ATAG-Wombat] 2001-08-25
- When several views co-exist, each may have a
selection, but only one is active, called the "current user selection."
User selections may be rendered specially (e.g., graphically
highlighted).
- Current
Viewport [UAAG10]
- See Views, viewports,
and current viewport UA.
- D
- Data [RFC2828] 03-12-2001
- Information in a specific physical representation,
usually a sequence of symbols that have meaning; especially a
representation of information that can be processed or produced by a
computer.
- Data Category
[P3P] 2001-02-27
- A significant attribute of a data element or data
set that may be used by a trust engine to determine what type of
element is under discussion, such as physical contact information.
P3P1.0 specifies a set of data categories.
- Data Element [P3P]
2001-02-27
- An individual data entity, such as last name or
telephone number. For interoperability, P3P1.0 specifies a base set of
data elements.
- Data Model [WCAG10] [WCAG20] ISSUE
- The product of the database design process which
aims to to identify and organize the required data logically and
physically. A data model says what information is to be contained in a
database, how the information will be used, and how the items in the
database will be related to each other.
Example: A data model might specify
that a customer is represented by a customer name and credit card
number and a product as a product code and price, and that there is a
one-to-many relation between a customer and a product. It can be
difficult to change a database layout once code has been written and
data inserted. A well thought-out data model reduces the need for such
changes. Data modelling enhances application maintainability and future
systems may re-use parts of existing models, which should lower
development costs. A data modelling language is a mathematical
formalism with a notation for describing data structures and a set of
operations used to manipulate and validate that data. One of the most
widely used methods for developing data models is the
entity-relationship model. The relational model is the most widely used
type of data model. Another example is
NIAM.
- Data Model [DOM1]
2001-03-10
- A data model is a collection of descriptions of data
structures and their contained fields, together with the operations or
functions that manipulate them.
- Data Resource [CC-PP] 2003-03-05
- A data object that can be transferred across a
network. Data resources may be available in multiple representations
(e.g. multiple languages, data formats, size, resolutions) or vary in
other ways.
- Data Set [P3P] 2001-02-27
- A known grouping of data elements, such as
"user.home.postal". The P3P1.0 base data schema specifies a number of
data sets.
- Data Set GENERIC 2001-03-17 Dublin Core Def.
- A dataset is information encoded in a defined
structure (for