Any agency or department of the United States as defined in 44 U.S.C. 3502, and the United States Postal Service.


A change to existing ICT that affects interoperability, the user interface, or access to information or data.


Software designed to perform, or to help the user to perform, a specific task or tasks.

Assistive Technology (AT)

Any item, piece of equipment, or product system, whether acquired commercially, modified, or customized, that is used to increase, maintain, or improve functional capabilities of individuals with disabilities.

Audio Description

Narration added to the soundtrack to describe important visual details that cannot be understood from the main soundtrack alone. Audio description is a means to inform individuals who are blind or who have low vision about visual content essential for comprehension. Audio description of video provides information about actions, characters, scene changes, on-screen text, and other visual content. Audio description supplements the regular audio track of a program. Audio description is usually added during existing pauses in dialogue. Audio description is also called “video description” and “descriptive narration”.

Authoring Tool

Any software, or collection of software components, that can be used by authors, alone or collaboratively, to create or modify content for use by others, including other authors.

Closed Functionality

Characteristics that limit functionality or prevent a user from attaching or installing assistive technology. Examples of ICT with closed functionality are self-service machines, information kiosks, set-top boxes, fax machines, calculators, and computers that are locked down so that users may not adjust settings due to a policy such as Desktop Core Configuration.


Electronic information and data, as well as the encoding that defines its structure, presentation, and interactions.


Logically distinct assembly of content (such as a file, set of files, or streamed media) that: functions as a single entity rather than a collection; is not part of software; and does not include its own software to retrieve and present content for users. Examples of documents include, but are not limited to, letters, email messages, spreadsheets, presentations, podcasts, images, and movies.

Existing ICT

ICT that has been procured, maintained or used on or before January 18, 2018.


A tangible device, equipment, or physical component of ICT, such as telephones, computers, multifunction copy machines, and keyboards.

Information Technology

Shall have the same meaning as the term “information technology” set forth in  40 U.S.C. 11101(6).

Information and Communication Technology (ICT)

Information technology and other equipment, systems, technologies, or processes, for which the principal function is the creation, manipulation, storage, display, receipt, or transmission of electronic data and information, as well as any associated content. Examples of ICT include, but are not limited to: computers and peripheral equipment; information kiosks and transaction machines; telecommunications equipment; customer premises equipment; multifunction office machines; software; applications; Web sites; videos; and, electronic documents.


A set of systematically arranged alphanumeric keys or a control that generates alphanumeric input by which a machine or device is operated. A keyboard includes tactilely discernible keys used in conjunction with the alphanumeric keys if their function maps to keys on the keyboard interfaces.


Text, or a component with a text alternative, that is presented to a user to identify content. A label is presented to all users, whereas a name may be hidden and only exposed by assistive technology. In many cases, the name and the label are the same.


A set of selectable options.


Text by which software can identify a component to the user. A name may be hidden and only exposed by assistive technology, whereas a label is presented to all users. In many cases, the label and the name are the same. Name is unrelated to the name attribute in HTML.

Non-Web Document

A document that is not: a Web page, embedded in a Web page, or used in the rendering or functioning of Web pages.

Non-Web Software

Software that is not: a Web page, not embedded in a Web page, and not used in the rendering or functioning of Web pages.

Operable Part

Hardware-based user controls for activating, deactivating, or adjusting ICT.

Platform Accessibility Services

Services provided by a platform enabling interoperability with assistive technology. Examples are Application Programming Interfaces (API) and the Document Object Model (DOM).

Platform Software

Software that interacts with hardware or provides services for other software. Platform software may run or host other software, and may isolate them from underlying software or hardware layers. A single software component may have both platform and non-platform aspects. Examples of platforms are: desktop operating systems; embedded operating systems, including mobile systems; Web browsers; plug-ins to Web browsers that render a particular media or format; and sets of components that allow other applications to execute, such as applications which support macros or scripting.

Programmatically Determinable

Ability to be determined by software from author-supplied data that is provided in a way that different user agents, including assistive technologies, can extract and present the information to users in different modalities.

Public Facing

Content made available by an agency to members of the general public. Examples include, but are not limited to, an agency Web site, blog post, or social media pages.

Real-Time Text (RTT)

Communications using the transmission of text by which characters are transmitted by a terminal as they are typed. Real-time text is used for conversational purposes. Real-time text also may be used in voicemail, interactive voice response systems, and other similar application.

Revised 508 Standards

The standards for ICT developed, procured, maintained, or used by agencies subject to Section 508 of the Rehabilitation Act as set forth in 508 Chapters 1 and 2 (36 CFR part 1194, Appendix A), and Chapters 3 through 7 (36 CFR part 1194, Appendix C).


Programs, procedures, rules, and related data and documentation that direct the use and operation of ICT and instruct it to perform a given task or function. Software includes, but is not limited to, applications, non-Web software, and platform software.

Software Tools

Software for which the primary function is the development of other software. Software tools usually come in the form of an Integrated Development Environment (IDE) and are a suite of related products and utilities. Examples of IDEs include Microsoft® Visual Studio®, Apple® Xcode®, and Eclipse Foundation Eclipse®.


The signal transmission, between or among points specified by the user, of information of the user’s choosing, without change in the form or content of the information as sent and received.


Device or software with which the end user directly interacts and that provides the user interface. For some systems, the software that provides the user interface may reside on more than one device such as a telephone and a server.


A sequence of characters that can be programmatically determined and that expresses something in human language.


Equipment that enables interactive text based communications through the transmission of frequency-shift-keying audio tones across the public switched telephone network. TTYs include devices for real-time text communications and voice and text intermixed communications. Examples of intermixed communications are voice carry over and hearing carry over. One example of a TTY is a computer with TTY emulating software and modem.

Variable Message Signs (VMS)

Non-interactive electronic signs with scrolling, streaming, or paging-down capability. An example of a VMS is an electronic message board at a transit station that displays the gate and time information associated with the next train arrival.

Voice over Internet Protocol (VoIP)

A technology that provides real-time voice communications. VoIP requires a broadband connection from the user’s location and customer premises equipment compatible with Internet protocol.

Web page

A non-embedded resource obtained from a single Universal Resource Identifier (URI) using HyperText Transfer Protocol (HTTP) plus any other resources that are provided for the rendering, retrieval, and presentation of content.