Glossary
Searchable terminology from accessibility, web standards, and related fields.
899 results found in Assistive Technology.
- Dwell Activation (Dwell Click, Dwell Selection)
- An input method where an action is triggered by maintaining focus on a target for a specified period of time (the dwell time). Commonly used with eye tracking and head tracking systems, dwell activati…
- Dwell Time (Gaze Dwell, Fixation Duration)
- The length of time a user must maintain their gaze on a target element to trigger a selection in eye gaze technology systems. Dwell time is a critical parameter in gaze-based interfaces: too short and…
- Dwell-Based Selection (Dwell Selection, Dwell Time Selection)
- An interaction technique used in eye-gaze and head-tracking interfaces in which holding the cursor over a target for a fixed duration (the 'dwell time', typically 300-1000 ms) triggers a selection, re…
- Dynamic Content (Dynamic Web Content, Live Content)
- Dynamic content refers to web page elements that change or update after the initial page load, either automatically (such as news tickers, stock prices, or chat messages) or in response to user intera…
- Dynamic Difficulty Adjustment (DDA, Adaptive Difficulty)
- A system design approach that automatically or manually adjusts the precision, complexity, or challenge level of feedback and interaction based on the user's skill level and progress over time. Origin…
- Dynamic Keyboard (Adaptive Keyboard, Self-Adjusting Keyboard)
- An assistive technology concept in which a keyboard automatically adjusts its input parameters — such as key repeat rate, debounce time, and acceptance delay — based on the user's typing patterns and …
- E-Tran Frame (Eye-Transfer Frame, Eye-Pointing Frame, ETRAN)
- A low-technology augmentative and alternative communication (AAC) device consisting of a transparent frame or board that allows a person to communicate by directing their eye gaze toward symbols, lett…
- EMG Switch (Electromyography Switch, Muscle Signal Switch)
- An assistive technology switch that detects electrical signals produced by muscle contractions (electromyography) to generate a switch activation. EMG switches can detect even very small muscle moveme…
- EVITA (Enabling Visually Impaired Table Access)
- A specialized table browser developed at the University of Manchester designed to enable visually impaired users to navigate, browse, and read HTML data tables non-visually in a manner analogous to ho…
- EdgeWrite (Edge Write)
- A gestural text entry method that uses the physical edges and corners of a square input area to guide character formation. Unlike traditional handwriting recognition that analyzes the full path of a s…
- Educational Technology (EdTech, Learning Technology, Instructional Technology)
- The use of technological tools and resources to facilitate teaching and learning. In accessibility contexts, educational technology encompasses assistive tools designed to support students with disabi…
- Eigenfaces
- A computer vision technique for face recognition that uses Principal Component Analysis to represent faces as a linear combination of standardized face components (eigenvectors derived from a training…
- Eight-Dot Braille (8-Dot Braille, Computer Braille)
- An extended braille system that adds two additional dots below the standard six-dot braille cell, creating a 2x4 matrix of eight dots that can represent 256 unique characters (compared to 64 in standa…
- Electrolarynx (Artificial Larynx, Electric Larynx, EL Device, Throat Vibrator)
- A handheld battery-powered device that produces mechanical vibrations to generate speech for people who have lost their larynx (voice box), typically due to laryngeal cancer surgery. The device is hel…
- Electromagnetic Actuation (EM Actuation)
- A method of producing physical movement using electromagnetic fields generated by electric coils. In accessibility contexts, electromagnetic actuation is used to move tactile elements — such as magnet…
- Electromagnetic Tracking (Magnetic Tracking, 6-DOF Tracking)
- Electromagnetic tracking is a position and orientation sensing technology that uses electromagnetic fields to determine the location and rotation of a sensor in three-dimensional space. Systems like t…
- Electronic Assistive Technology (EAT, Electronic AT)
- Computer-based devices and systems that enable people with severe disabilities to perform tasks they would otherwise be unable to accomplish, including communication, environmental control, mobility, …
- Electrooculogram (EOG, Electrooculography)
- The electrooculogram (EOG) is a technique for measuring the electrical potential difference between the front and back of the eye using surface electrodes placed around the eyes. This corneal-retinal …
- Emacspeak (The Emacspeak Audio Desktop)
- A free, open-source speech output system built on top of the Emacs text editor that provides complete auditory access to a computing environment for blind and visually impaired users. Created by T. V.…
- Embodied Conversational Agent (ECA, Virtual Agent, Animated Agent)
- A computer-generated animated character designed to interact with human users using multiple simultaneous communication channels — typically speech, eye gaze, facial expression, head and body posture,…