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Accessibility Glossary Terms

  • 508
    Section 508 of the Rehabilitation Act was enacted to eliminate barriers in information technology, to make available new opportunities for people with disabilities, and to encourage development of technologies that will help achieve these goals. Under Section 508 (29 U.S.C. § 794d), Federal Agencies must give disabled employees and members of the public access to information that is comparable to the access available to others.
  • Accelerator keys
    Usually combinations of characters that allow users to make software commands instead of interacting with menu options or different levels of a user interface, also known as keyboard shortcuts.
  • Accessibility
    The measure of a web page's usability by persons with one or more disabilities.
  • Alternative Text
    Short text used described images---usually 125 characters or less.
  • Assistive technologies
    Technologies (software or hardware) that increase, maintain, or improve the functional capabilities of individuals with disabilities when interacting with computers or computer-based systems.
  • Audio browsers
    Web browsers that provides a text-to-speech capability for the blind and visually impaired.
  • Braille terminal
    Machines that convert text on a screen to braille by raising bumps through holes on a flat surface.
  • Captioning
    The art of adding captions to a television program or movie.
  • Captions
    A textual representation of sounds--usually associated with television programming or movies; captions are meant to display in real time and to capture speech sounds and sounds beyond speech in some cases.
  • Clickability cues
    A visual indication that a given word or item on a Web page is clickable. Cues that can be used to indicate the clickability of an item include color, underlining, bullets, and arrows.
  • Disability
    A limitation in an ability
  • Early adoptors
    A user who has a tendency to embrace new technology before the majority.
  • Graceful Degradation
    When a site utilizes new technology, if disabled, the content maintains effectiveness for the users.
  • Heat maps
    Color-based representations of areas of interest/focus points; generally associated with eye-tracking software.
  • Internationalization
    A system whose primary design has been developed to work in multiple languages and in the cultural contexts of different locales.
  • Late adopters
    Individuals who are hestitant to adopt new technology.
  • Localization
    Customizing or personalizing a national or international product for a local market.
  • Long Descriptions
    Descriptions that are written for complex figures and tagged via the long desc attribute; though not currently supported by most Web browsers, the long desc attribute is a planned feature in the next iteration of Firefox.
  • Luminance Contrast Ratio
    A measure of the difference between foreground and background; specific minimal values are recommended via WCAG 2.0.
  • Programmatic Focus
    Where the computer's focus is on a Web page.
  • Screen reader
    A software program used to allow reading of content and navigation of the screen using speech or Braille output. Used primarily by people who have difficulty seeing. JAWS and NVDA are examples.
  • Section 508 [see also 508]
    Section 508 of the Rehabilitation Act was enacted to eliminate barriers in information technology, to make available new opportunities for people with disabilities, and to encourage development of technologies that will help achieve these goals. The law applies to all Federal agencies when they develop, procure, maintain, or use electronic and information technology. To learn more go to 508.gov.
  • Transcript
    A text only version of what's said in a movie or television program; they are not real time and they generally are limited to speech only; they are not a recommended substitute for captions.
  • Visual Focus
    Where the user's focus is on a Web page; generally represented by a dashed box that appears around items on the page and associated with tabbing.
  • WCAG 2.0
    The Web Content Accessibility Guidelines (WCAG) 2.0 is focused on providing an international technical standard for web content. It has 12 guidelines that are organized under four principles: perceivable, operable, understandable, and robust. The guidelines each have a testable success criteria, which are at three levels: A, AA, and AAA.