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.

Active voice makes subjects do something (to something). For example, in "John caught the ball," the verb "caught" is in the active voice: John did to the ball what the verb caught expresses.

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.'

A mini-software program that a Java- or ActiveX-enabled browser downloads and uses automatically.

Technologies (software or hardware) that increase, maintain, or improve the functional capabilities of individuals with disabilities when interacting with computers or computer-based systems.

A website 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.

Banners are graphic images that commonly function as Web-based billboards. Banner ads generally appear toward the top-center of the screen, and are used as attention-grabbing links to other sites.

Breadcrumbs are a navigation element that allows users to orient themselves within a website, or efficiently move to one of the intermediate pages. Breadcrumbs are usually placed near the top of the page (generally immediately beneath the browser's address bar). For example, if users are reading about the features and benefits of "Widget X," breadcrumbs might show the following information: Home > Products > Widget X > Features/Benefits. Breadcrumbs allow users to find their way to the homepage and ensure that they won't easily become lost. Breadcrumbs should be designed so that users can click on any of the words in the breadcrumb string to jump to that section of the website.

A method used to identify categories that are inherent in a set of items. The goal of card sorting is to understand how a typical user views a given set of items. Card sorting is usually done by writing items on individual paper cards, and then asking users to group together similar cards. The grouping information from all card sorters is then combined and analyzed using cluster analysis software.

A menu structure where submenus open when the user selects a choice from a menu. Cascading menus are particularly useful in hierarchically-complex websites.

A control element that a user can click to turn an option on or off. When the option is on, an "X" or "v" appears in the box. Check boxes are conventionally used when users may select one or more items from a list of items.

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.

Occurring on the client side of a client-server system. JavaScript scripts are client-side because they are executed by the user's browser (the client). In contrast, CGI scripts are server-side because they run on the Web server.

An inspection method for evaluating the design of a user interface, with special attention to how well the interface supports "exploratory learning," i.e., first-time use without formal training. The evaluation is done by having a group of evaluators go step-by-step through commonly used tasks. It can be performed by evaluators in the early stages of design, before performance testing is possible.

The maximum rate at which Web pages are downloaded to a user's computer. Connection speed is often quoted in bps (bits per second). Common connection speeds include dial-up (modem) at 28,800 to 56,000 bps, DSL/cable at approximately 500,000 bps, and T1 at up to 1,500,000 bps.

A Web page designed to convey specific information to a user. Content pages are often found two or three clicks deep within a website. The defining characteristic of a content page is a reliance on text, graphics, and pictures that are designed to convey information on a given subject to users.

In a Web context, continuous text comprises sentences and paragraphs. See also ‘Prose text.'

A visually well-defined location on a page where users may enter data.

A measure of the percent of the screen that is filled with text and graphics.

The location in a website where a given user goes after clicking on a link. See also ‘Target page.'

The amount of time required for a requested page to fully appear on a user's screen.

Drop-down lists are screen-based controls in which one list item shows, and the remaining list items are hidden until users click on a downward-facing arrow. Drop-down lists allow designers to preserve screen real estate while maintaining the ability to present a full suite of options to users.

A link that is found in the middle of prose or continuous text. Embedded links are often used to provide users with the definitions of terms or to lead them to supporting or related information.

The entry field, which is also known as a data or text entry field, is employed when users are required to make text or data entries, including keywords, commands, quantities, etc. Expert evaluation or Expert review See ‘Heuristic evaluation.'

The fold is defined as the lowest point where a Web page is no longer visible on a computer monitor or screen. Where on a Web page the fold falls is a function of the monitor size, the screen resolution, and the font size selection. The information that is visible when a Web page first loads is considered to be ‘above the fold.' Those regions of the same Web page that are visible only by scrolling are considered to be ‘below the fold.'

A feature supported by most browsers that enables the designer to divide the display area into two or more sections (frames). The contents of each frame behave like different Web pages.

An automated action that provides summary information on where a link will take a user prior to the user clicking on the link. Often, glosses appear as a small ‘pop-up' text box adjacent to a link. The gloss appears as the user moves the mouse over the link that is programmed with the gloss.

The title, subtitle, or topic that stands at the top or beginning of a paragraph or section of text.

An inspection method for finding certain types of usability problems in a user interface design. Heuristic evaluation involves having one or more usability specialists individually examine the interface and judge its compliance with recognized usability principles. These usability principles are the "heuristics" from which the method takes its name.

A graphic designed to assist users' navigation of a website. Regions of the graphic are designed to be clickable.

Index links function as a table of contents—they provide users a quick glance at the website organization, allows users to quickly ascertain where they want to go, and to navigate there directly from the homepage.

A word that is used as a reference point for finding other words or information using a search capability in a website.

The (usually) graphical banner at the top of a Web page that identifies the organization or group that hosts the website. The masthead typically contains the name of the organization and site (if different) and an organizational logo.

An action designed to identify where on a page links are located. Minesweeping involves the user rapidly moving the cursor or pointer over a page, watching to see where the cursor or pointer changes to indicate the presence of a link. See also ‘Mouseover.'

A Web interaction wherein some visually-apparent change occurs to an item when the user's cursor/pointer is placed over the item. Examples of visually-apparent change includes links highlighting (words, images, etc.), cursors/pointers changing shape, or menus opening. See also ‘Minesweeping.'

A Web page that contains no content and that is designed solely to direct or redirect users. Navigation pages may be designed as homepages, site maps, site overviews, etc.

An open list is a screen-based control where either all of the list items are immediately visible on the screen, or where several list items are immediately visible to the user, and the remaining list items can be viewed by scrolling the list.

Page titles refer to the text located in the browser title bar (this is the bar found at the very top of the screen of common browsers).

A website design methodology that requires users to follow a series of "Next page" links to read an entire article. Moving from page-to-page is an alternative to scrolling through long pages.

Visually and thematically-defined sections of a Web page. Panels are frequently placed in the left and right margins of pages. Panels often contain navigation aids, including related links. Content is not usually placed in left or right panels.

Voice is a grammatical feature of English verbs. Passive voice permits subjects to have something done to them (by someone or something). For example, "The ball was caught by John." Some argue that passive voice is more indirect and wordier than active voice.

The route taken by a user as they move through a website. The path can be shown by breadcrumbs.

The goals set for user behaviors on an individual Web page or a series of Web pages. These objectives usually are stated in terms of the time to correctly select a link, the overall accuracy of selecting links, the average time to select a target page, etc.

A usability test that is characterized by having typical users perform a series of tasks where their speed, accuracy and success are closely monitored and measured. Physical consistency Physical consistency refers to the "look and feel" of a website. Physically consistent Web pages will have logos, headers, and navigation elements all located in the same place. The pages also will use the same fonts and graphic elements across all pages in the site.

A software module that adds a specific feature or service to a larger system. For example, there are a number of plug-ins for common browsers that enable them to display different types of audio and video.

A term used to describe conventional Web surfing behavior. When a user visually identifies a link they wish to follow, they place their mouse pointer over the link (point) and depress the appropriate button on the mouse (click). See also ‘Mouseover.'

A pop-under or pop-up is a window that is automatically invoked when a user loads a Web page. Pop-unders appear "below" the active browser window, whereas pop-ups appear "above" the active window and can obscure screen contents.

The goals set for user attitudes toward individual Web pages or an entire website. The objectives are usually set and measured using questionnaires. These objectives include information concerning user acceptance and user satisfaction.

Ordinary writing. In a Web context, prose text comprises sentences and paragraphs. See also ‘Continuous text.'

Pushbuttons are screen-based controls that contain a text label or an image (or both). Pushbuttons are used to provide quick and convenient access to frequently-used actions. The pushbutton control is always activated with a single click of a mouse button. Clicking on pushbuttons should cause the indicated action to take place, i.e., "Search." Do not use pushbuttons to move from one location to another in a website.

A screen-based control used to select one item from a list of mutually-exclusive items (i.e., use radio buttons when only one item in a list of several items can be selected).

Information that automatically appears on the screen during a Web-based slideshow presentation, or while viewing a multimedia Web page.

An information-retrieval method whereby users look quickly through a Web page looking for target information (headers, keywords, etc.). Scanning can be a quick and efficient information-retrieval method if Web pages are designed to accommodate scanning.

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.

A screenful is defined as that portion of a Web page that is visible on any given user's monitor or screen at any given point in time. The size of the screenful is determined by the user's monitor size, screen resolution settings, and the user's selected font size.

The scroll bar is visible along the right edge of common browsers. It is defined by a movable box that runs on a vertical or horizontal axis.

A graphic or other page element that may visually impede a user from scrolling to the true top or bottom of a page. Misplaced headers, horizontal lines, or sections of text in very small fonts may act as scroll stoppers.

A method of traversing a Web page wherein users either roll the scroll wheel on their mouse, or manually move the scroll bar located on the right side of their browser's screen.

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. Under Section 508 (29 U.S.C. § 794d), agencies must give disabled employees and members of the public access to information that is comparable to the access available to others.

Menus that involve multiple choices that must be made in some predetermined order, with the impact of a given choice constrained by the sum total of all previous choices.

Occurring on the server side of a client-server system. For example, on the Web, CGI scripts are server-side applications because they run on the Web server. In contrast, JavaScript scripts are client-side because they are executed by the browser (the client). Java applets can be either server-side or client-side depending on which computer (the server or the client) executes them.

Menus that simultaneously display choices from multiple levels in the menu hierarchy, providing users with the ability to make menu choices in any order.

A clickable, graphic- or text-based display of a website's hierarchy.

A set of statements that specify presentation of a document. Style sheets may have three different origins: they may be written by content providers, created by users, or built into browsers or plug-ins.

A graphical navigation element that is most often placed at the top of a Web page. Effective tabs should be designed so that they resemble real-world file folder tabs.

A phrase or short sentence placed directly below a Web page's masthead. The tagline functions to quickly identify the purpose of the website. It may be a subtitle, an organizational motto, or a vision or purpose statement.

The location in a site where a user will find the information they are seeking. See also 'Destination page.'

A method used to identify and understand the activities to be performed by users when interacting with a website.

A small copy of a larger image.

When entering data that may be sensitive (e.g., credit card or social security numbers), many websites will disconnect ('time out') if a user has not interacted with the browser in a set amount of time.

URL is an abbreviation for Uniform Resource Locator. Every Web page has a URL that is used to identify the page and the server on which the page resides.

Usability testing includes a range of test and evaluation methods that include automated evaluations, inspection evaluations, operational evaluations and human performance testing. In a typical performance test, users perform a variety of tasks with a prototype (or an operational system) while observers note what each user does and says while performance data are recorded. One of the main purposes of usability testing is to identify issues that keep users from meeting the usability goals of a website.

Screen-based controls that are used to interact with a website and other systems. Widgets include pushbuttons, selection lists, radio buttons, sliders, etc.

Within-page links are used on content pages that contain several (e.g., three or more) screenfuls of information. Within-page links are best arranged as a table of contents for the page. Within-page links allow users to skip through textual information, resulting in a more efficient information-finding process. See also 'Anchor links.'