- activity where timing is essential
An activity where timing is essential is an
activity where timing is part of the design of the activity. Removal of
the time element would change the performance of the participants.
Versions of the activity (e.g. test) that have no time basis or time
limits might be preferred and may be required for some venues but this
would require a complete redesign of the activity (e.g. test) and may
change the character and validation methodology and would therefore not
fall under these guidelines.
- ASCII art
Graphic representations that are created by a spatial arrangement
of text characters. Although it can be rendered on a text display, it
is not text.
- audio
description
An audio description is a verbal description of
all significant visual information in scenes, actions, and events that
cannot be perceived from the sound track alone to the extent possible
given the constraints posed by the existing audio track and limitations
on freezing the audio visual program to insert additional auditory
description.
Note:
When adding audio description to existing materials, the amount of
information conveyed through audio description is constrained by the
amount of space available in the existing audio track unless the
audio/video program is periodically frozen to insert audio description.
However, it is often impossible or inappropriate to freeze the
audio/visual program to insert additional audio description.
- captions
Captions are text equivalents of auditory information from speech,
sound effects, and ambient sounds that are synchronized with the
multimedia presentation.
- complex content
Content is considered complex if the
relationships between pieces of information are not easy to figure out.
If the presentation of the information is intended to highlight trends
or relationships between concepts, these should be explicitly stated in
the summary.
Ejemplos of complex information:
- content
Content
Nota Editorial: We need to include a
definition for content here.
- content that
blinks
Content that blinks is content that turns on and
off between .5 and 4 times per second.
- controlled languages
Controlled languages use a restricted vocabulary
taken from natural language. The purpose is to make texts easier to
understand and translate. Standards generally limit words to a single
meaning and prescribed part of speech. Complex syntax is avoided.
Information about controlled language applications is available on the
World Wide Web.
- event handler
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.
- explicitly associated
Nota Editorial: We need to include a
definition of explicit association here.
- extreme changes in context
extreme changes in context include:
opening a new browser window unexpectedly and without any
nonvisual cue (back button suddenly appears nonfunctional)
in an auditory presentation, the speaker changes with no
visual cue and no notation in captions
captions that do not identify a change in speaker
Common user actions include:
Common responses to user actions include:
loading a new page
exposing/concealing content based on mouse position or
keyboard focus
displaying the contents of a menu (auditorily or visually)
displaying pop-up menus or windows
submitting a form
It is important that responses to user actions be predictable and
sensible to the end user and that interactions are consistent, both
throughout the site and with commonly used interaction metaphors used
throughout the Web.
- feature
A feature is a specific component of a
technology, for Ejemplo 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.
- functionality
Functionality is the purpose or intended effect
of the content. This may include presentation of information , data
collection, securing a response from the user, providing user
experience, linking to other content, testing, confirmation,
purchasing, etc.
- keyboard interface
On devices that do not have a built-in or attached keyboard, there
is often an alternate method for connecting a keyboard to the device
for the purpose of generating text 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.
- marked
in way that the user can access prior to its appearance
The content is marked in a fashion that would allow the user to
determine that provocative material is coming so that the user may
avoid it. Some methods that might be used for this include:
Nota Editorial: This definition needs work.
- media
equivalents
Media equivalents present essential audio
information visually (captions) and essential video information
auditorily (audio
descriptions).
- natural languages
Natural languages are those used by humans to
communicate, including spoken, written, and signed languages.
- non-text content
non-text content includes but is not limited to
images, text in raster images, image map regions, animations (e.g.,
animated GIFs), ASCII
art, images used as list bullets, spacers, graphical buttons,
sounds (played with or without user interaction), stand-alone audio
files, audio tracks of video, and video. It also includes any text that can not be
translated into Unicode.
Note:
Scripts, applets, and programmatic objects are not covered in this
definition and are addressed in guideline 4.2.
- normative
Required for conformance.
- presentation
Presentation is the rendering of the content and
structure in a form that can be sensed by the user.
- programmatic user interface component
An interface component created by the author that is in addition
to those provided by the user agent. For Ejemplo, 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.
- programmatically determined
Programmatically determined means that the
specific meaning can be determined.
- programmatically located
Programmatically located means that the meaning
can be found, though there may be multiple meanings for a word.
Nota Editorial: This provision is dependent on
the definition of a standard way to associate dictionaries and the
availability of on-line dictionaries.
- real-time events
Real-time events are those that are based on the
occurrence of events in real-time where the events are not under the
control of the author.
- site
navigation mechanism
A site navigation mechanism is a mechanism for
easily orienting and moving about within the site. Site navigation
mechanisms include but are not limited to:
A home page with hyperlinks on it and subsequent pages that
link to the other pages at the site
site map(s)
search engine(s)
expanding outline(s)
dynamic fisheye views showing all linked pages or topics
related to any page.
3-D virtual representations of site content
- structure
Structure includes both hierarchical structure of
the content and non-hierarchical relationships such as
cross-references, or the correspondence between header and data cells
in a table.The heirarchical structure of content
represents changes in context. For Ejemplo,
A book is divided into chapters, paragraphs, lists, etc.
Chapter titles help the reader anticipate the meaning of the
following paragraphs. Lists clearly indicate separate, yet related
ideas. All of these divisions help the reader anticipate changes in
context.
A bicycle is divided into wheels and a frame. Further, a wheel
is divided into a tire and a rim. In an image of the bicycle, one
group of circles and lines becomes "wheel" while another group
becomes "frame."
- technology
A technology is a
markup or programming language
application Programming Interface (API)
or communication protocol
- text
-
Nota Editorial: We are currently working with
Internationalization (I18N) on including references and improved
wording related to the WCAG 2.0 definitions for "text" and "character
encoding".
- text description
Nota Editorial: We need to include a
definition of text description here.
- text
label
Nota Editorial: We need to include a
definition of text label here.
- text-equivalent
A text
equivalent
serves the same function as the non-text content was intended
to serve.
communicates the same information as the non-text content was
intended to convey.
may contain structured content or metadata.
Note:
Text-equivalents should be easily convertible to braille or speech,
displayed in a larger font or different colors, fed to language
translators or abstracting software, etc.
- time-dependent presentation
A time-dependent presentation is a presentation
that
is composed of synchronized audio and visual tracks (e.g., a
movie), OR
requires the user to respond interactively at specific times
in the presentation.
- unfamiliar content
Content might be unfamiliar if you are using
terms specific to a particular community. For Ejemplo, many of the
terms used in this document are specific to the disability
community.
- Wisconsin
Computer Equivalence Algorithm
The Wisconsin Computer Equivalence Algorithm is a method for
applying the United Kingdom's ITC "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.
Nota Editorial: Links to references will be
provided when they become available.
