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  • A/B Testing
    Determining which of two alternatives is better received by the target audience.
  • About Box
    A standard dialog box that provides the credits and revision information of computer software.
  • Above the fold [or Above-the-fold]
    The region of a Web page that is visible without scrolling. The area above the fold will vary according to a user's monitor size and their resolution settings. The region above the fold is called a screenful.
  • 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.
  • Acceptable margin of error
    Consideration for the number of acceptable errors in an experiment; a smaller margin of error indicates trustworthy results and a larger margin of error means the results are less consistent.
  • Accessibility
    The measure of a web page's usability by persons with one or more disabilities.
  • Accumulator
    A control that allows the selection of multiple items from a list into a new functional group.
  • Active listening
    Interviewing technique in which the interviewer pays attention, shows acknowledgement, and provides feedback to encourage the conversation.
  • Active voice
    Active voice makes subjects do something (to something). For example, in "Jill selected the link," the verb "selected" is in the active voice.
  • Ad hoc navigation
    Embedded or in-page links that are more editorial than architectural.
  • Affordance
    When a control behaves as its appearance suggests.
  • ALT text or Alternative text
    An attribute used in HTML and XHTML documents to provide a short description of an image.
  • Alternative Text
    Short text used described images---usually 125 characters or less.
  • Analysis paralysis
    Overanalyzing or overthinking a situation or subject to the point that decision making is delayed.
  • Analytics
    See Web analytics
  • Anchor links
    Anchor links can be used on content pages that contain several (usually three or more) screenfuls of information. Anchor links allow users to skip through textual information, resulting in a more efficient information-finding process. Anchor links are best arranged as a table of contents for the page. See also "Within-page links." Also known as jump links.
  • Animation
    A simulation of movement by the rapid appearance of images in sequence.
  • Anti-aliasing
    Smoothing the jagged appearance of diagonal lines in a bitmapped image. The pixels that surround the edges of the line are changed to varying shades of gray or color in order to blend the sharp edge into the background. This technique is also called "dithering."
  • Applet
    Small add on program that runs one specific task within the scope of a larger application. Example A mini-software program that a Java- or Active X-enabled browser downloads and uses automatically.
  • 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.
  • Auto-complete
    A feature that helps finish what a user is typing by predicting what the user wants to input based on previous or popular entries.
  • Auto-tabbing
    A Web site feature whereby the data entry cursor automatically moves from one entry field to the next as a user enters a pre-determined number of characters. For instance, when entering phone number data in three separate entry fields of three digits, three digits, four digits, the data entry cursor would auto-tab from the first field to the second field once the user has entered three digits, and again from the second field to the third field once the user has entered another three digits.