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WAI: Strategies, guidelines, and resources to make the Web accessible to people with disabilities

[DRAFT] Basic Glossary for WAI Documents

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This glossary clarifies the meaning of words used in WAI documents. Related resources include:

alternative equivalents
see equivalent alternative
assistive technology
Any item, piece of equipment, product, system or software, whether acquired commercially off the shelf, modified, or customized, that is used to increase, maintain, or improve functional capabilities of individuals with disabilities.
audio descriptions
Audio description (also called "described video") is an equivalent alternative that provides aural information about actions, body language, graphics, and scene changes in a video. Audio descriptions are commonly used by people who are blind or have low vision, although they may also be used as a low-bandwidth equivalent on the Web. An audio description is either a pre-recorded human voice or a synthesized voice (recorded or automatically generated in real time). The audio description must be synchronized with the auditory track of a video presentation, usually during natural pauses in the auditory track.
authoring tool
Any software or service that is used to produce content for publishing on the Web. Authoring tools include Web content editors, document conversion tools, and software that generate Web content from databases.
Captions are equivalent alternatives that consist of a text transcript of the auditory track of a movie (or other video presentation) and that is synchronized with the video and auditory tracks. Captions are generally rendered graphically. They benefit people who are deaf or hard-of-hearing, and anyone who cannot hear the audio (for example, someone in a noisy environment).
The state of a product or service when it satisfies all the requirements of a given specification.
A feature is that is obsolete or replaced by a newer feature and should no longer be used.
device independence
The use of a webpage or event handler with any kind of input device. Scripting should be device-independent or provide multiple input and output options for different devices. For example, onDblClick requires a mouse; there is no keyboard equivalent for double clicking. Input devices may include pointing devices (such as the mouse), keyboards, Braille devices, head wands, microphones, and others.
equivalent alternative
An equivalent alternative is content that is an acceptable substitute for other content that an end-user may not be able to access. An equivalent alternative fulfills essentially the same function or purpose as the original content upon presentation to the end-user. Equivalent alternatives include text alternatives, which present a text version of the information conveyed in non-text content such as graphics and audio clips. Equivalent alternatives also include "media alternatives", which present essential audio information visually (captions) and essential video information auditorily (audio descriptions).
graceful transformation
When a browser or media player changes the presentation of a document, the new presentation offers the same functionality as the original.
Information in a specification that is not required for conformance but contributes to the correct use and implementation of the specification.
The ability of software and hardware to communicate meaningfully on diverse machines from multiple vendors.
keyboard equivalent
Key or key combination that activates an application function that is usually activated by another input or control device such as a voice input or pointing device.
linearized content
A presentation that arranges web content in a sequential order. For example, one form of linearization changes side-by-side displayed content into a one column format. To be usable, a linearization should arrange content in a logical reading order.
markup language
A markup language is a syntax and/or set of rules to manage content and structure of a document or object (for example, HTML , SVG , or MathML).
meta data
Data that describes, highlights and/or explains other data. This includes items such as authorship, key words, character set, publication dates, title information and language. The inclusion of metadata in a web document helps indexing, searching processes and semantic analysis.
natural language
A language used by people to communicate with each other, opposed to e.g. a computer language.
Descriptions or prescriptions that lie outside the normative criteria of a specification.
Criteria that must be satisfied for conformance with a given specification.
real-time events
An event that is reported or recorded as it occurs — For example, in real time captioning text captions are displayed as the text is spoken.
Transformation of machine-oriented information into a form perceivable and usable to a human user. Document markup such as HTML or CSS may be incomprehensible to the human user, but a browser or media player may transform it into a meaningful form. For example the HTML element <em> indicates that emphasis is intended. The user agent may emphasize the content responding to CSS directions by changing font or tone of voice.
Techniques are informative suggestions and examples for ways in which the success criteria of a checkpoint might be satisfied and implemented.
A transcript is an equivalent text alternative for the sounds, narration, and dialogue in an audio clip or an auditory track of a multimedia presentation. For a video, the transcript can also include the description of actions, body language, graphics, and scene changes of the visual track.
user agent
Software to access Web content, including desktop graphical browsers, text browsers, voice browsers, mobile phones, multimedia players, plug-ins, and some software assistive technologies used in conjunction with browsers such as screen readers, screen magnifiers, and voice recognition software.
Web accessibility
Web accessibility means that the Web is designed so that people with disabilities can perceive, understand, navigate, and interact with it effectively, as well as create and contribute content to the Web.