Glossary

Searchable terminology from accessibility, web standards, and related fields.

840 results found in assistive technology.

Transcoding (Content transcoding, Web transcoding)
The process of converting or transforming web content from one format or structural representation to another to improve accessibility. In the context of screen reader access, transcoding can involve …
Turn-by-turn navigation (Step-by-step navigation, Guided navigation)
A navigation method that provides sequential walk-and-turn instructions to guide a user along a route without requiring prior knowledge of the environment. For people with visual impairments, turn-by-…
Two-Point Discrimination (Spatial Acuity, Tactile Acuity)
A measure of tactile sensitivity indicating the minimum distance at which two distinct points of contact on the skin can be perceived as separate rather than as a single point. Lower values indicate h…
UAAG (User Agent Accessibility Guidelines)
A set of guidelines from the W3C Web Accessibility Initiative that explains how to make user agents — browsers, media players, and other applications that render web content — accessible to people wit…
UI Agent (User Interface Agent, Browser Agent, AI Agent)
An AI-powered software system that can autonomously interact with graphical user interfaces on behalf of a user, performing tasks by interpreting natural language commands and translating them into in…
Ubiquitous Accessibility (Accessibility Everywhere)
A vision for accessibility in which individuals can invoke their needed assistive technologies or access features on any computing device they encounter, rather than being limited to personally owned …
Ultrasonic Sensor (Ultrasound Sensor, Proximity Sensor)
A device that measures distance to objects by emitting high-frequency sound waves and calculating the time it takes for the echo to return. In assistive technology, ultrasonic sensors are commonly use…
Unistroke Gesture (Single-Stroke Gesture, Unistroke)
A unistroke gesture is a shape or symbol drawn in a single continuous stroke on a touch screen or digitizer, which is then recognized by software as a specific command or input. In accessible interfac…
Universal Remote Console (URC, URC Framework)
The Universal Remote Console (URC) is an ISO/IEC standard framework (ISO/IEC 24752) that enables pluggable, alternative user interfaces for applications and devices. URC separates the user interface f…
User profile (User model, Personal needs and preferences profile, PNP)
A structured collection of data describing a user's characteristics, capabilities, preferences, and requirements for interacting with a computing system. In accessibility, user profiles inform how int…
Utterance-Based System (Utterance-Based AAC, Prestored Message System)
A type of augmentative and alternative communication (AAC) system that uses prestored phrases, sentences, or complete utterances rather than requiring users to construct messages word-by-word or lette…
VBraille (V-Braille, Vibration Braille)
A method for representing Braille characters on a smartphone touchscreen using vibration feedback. The screen is divided into a 3-row by 2-column grid matching a standard Braille cell layout, and the …
Variable Pointing Performance (Variable Pointing Ability, Intermittent Pointing Difficulty)
A condition where a person's ability to accurately use a pointing device (such as a mouse, trackpad, or touchscreen) fluctuates over time due to factors like physical impairments, fatigue, medication …
Verbosity (Verbosity Level, Screen Reader Verbosity)
Verbosity refers to the level of detail that an assistive technology — particularly a screen reader or voice browser — provides when announcing interface elements and content. Most screen readers allo…
Verbosity Level (Verbosity Setting, Detail Level)
A configurable setting that controls the amount of detail provided in text or audio descriptions of content, particularly for screen reader users and accessible data visualizations. Verbosity levels t…
Vibration Feedback (Haptic vibration, Vibrotactile feedback)
The use of controlled vibration patterns — varying in duration, interval, intensity, and spatial location — to convey information to a user through the sense of touch. In assistive technology for blin…
Vibro-Audio (Vibrotactile Audio, Vibro-Tactile)
Vibro-audio is a multimodal interaction technique that combines vibration feedback from a device's built-in motor with auditory cues to convey information non-visually. On touchscreen devices, vibro-a…
Vibro-audio Interface (VAI)
An assistive technology that combines vibration patterns and audio feedback to convey spatial and graphical information through touchscreen devices. Originally developed to make maps and diagrams acce…
Vibrotactile (Vibrotactile Feedback, Vibrotactile Stimulation)
A form of tactile feedback that uses mechanical vibrations applied to the skin to convey information. Vibrotactile stimulation typically operates at frequencies between 10-500 Hz and is perceived thro…
Vibrotactile Feedback (Vibrotactile, Vibrotactile Display, Tactile Vibration)
A form of haptic feedback that uses vibration patterns to convey information through the sense of touch. In accessibility, vibrotactile feedback provides an alternative or complement to visual and aud…