Glossary

Search results

Thermotactile Feedback(also: Thermal Feedback, Thermal Haptic Feedback, Thermotactile Display)

Thermotactile feedback is a form of haptic communication that conveys information through controlled temperature changes on the skin, using heating or cooling elements such as Peltier thermoelectric modules. In accessibility, thermotactile feedback offers an alternative to…

Tiger Embosser(also: ViewPlus Tiger, Tiger Braille Printer)

A brand of Braille embosser manufactured by ViewPlus Technologies that produces both Braille text and tactile graphics by pressing raised dots onto thick paper. Unlike traditional Braille embossers that only produce text, Tiger embossers can render graphical images with multiple…

Time Management

The ability to plan and control how time is allocated to specific activities. In the context of accessibility and assistive technology, time management support helps individuals with cognitive impairments organise and complete daily tasks by providing structured reminders,…

Time-Lapse Photography

A photographic technique that captures a series of still images at set intervals over a period of time. In accessibility contexts, time-lapse photography has been explored as an alternative to video capture for making visual content available to people with visual disabilities.…

Time-of-Flight Camera(also: TOF Camera, ToF Sensor, Depth Camera)

A type of camera sensor that measures the distance to objects by calculating the time it takes for emitted light (typically infrared) to travel to a surface and reflect back. Time-of-Flight cameras produce 3D depth maps of their environment in real time, making them useful in…

Tongue Display Unit(also: TDU, BrainPort, Tongue Electrotactile Display)

A sensory substitution device that presents visual or spatial information through an array of electrodes placed on the tongue. The tongue is ideal for electrotactile stimulation because it has a very high density of nerve endings, low and consistent electrical impedance due to…

Tool Substitution(also: Adaptive Tool Use, Alternative Tool Use)

The practice of using a different tool than what is specified or expected to accomplish a task, common among people with disabilities who adapt their approaches based on available resources, physical capabilities, or personal preference. In non-visual cooking, BLV individuals…

Tooltip(also: Form Field Tooltip, Accessible Name (PDF))

In PDF forms, a tooltip is the programmatic label associated with a form field that assistive technologies read aloud when the user reaches that field. Unlike HTML, PDF does not have a native label-to-field association, so the tooltip carries the accessible name. Best practice…

Total Communication

An approach to communication that incorporates all available modes and channels—including speech, gesture, facial expression, drawing, writing, pointing, props, and physical aids—rather than relying on a single modality. Total communication is particularly relevant for people…

Touch Exploration(also: Explore by Touch, Touch-Based Exploration)

An interaction method that allows users to discover on-screen content by moving their finger across a touchscreen, receiving audio feedback about elements under the fingertip. Touch exploration is fundamental to how blind and low-vision users navigate mobile devices through…

Touch Panel(also: Touch Tablet, Touch-Sensitive Panel, Digitizer Tablet)

A flat, pressure-sensitive input surface that detects the position of a finger or stylus when it makes contact. Unlike touchscreens, which combine display and input on the same surface, a touch panel is a separate input device placed over or alongside a display. In…

Touch Reader(also: Tactile Reader, Tactile Graphics Reader)

A person who reads and interprets information through touch, particularly tactile graphics, raised line drawings, and braille. Touch readers include blind and low-vision individuals who access spatial and graphical information through tactile media rather than vision. The skill…

Touch Sensor(also: Touch-Sensitive Sensor, Tactile Sensor)

An electronic component that detects physical contact or proximity of a finger or object on a surface. Touch sensors are used in accessible devices to enable direct tactile interaction, allowing blind users to trigger audio feedback by touching specific locations on a physical…

Touch-to-Explore(also: Touch Exploration, Explore by Touch)

An interaction mode used by touchscreen screen readers (such as VoiceOver on iOS and TalkBack on Android) where users drag their finger across the screen to discover and hear descriptions of interface elements beneath their fingertip. As the user's finger passes over buttons,…

Touchpad(also: Touch Tablet, Touch-Sensitive Pad)

A flat, pressure-sensitive input device that detects the position of a finger or stylus on its surface. In assistive technology contexts, touchpads are used as interactive overlays for tactile graphics and maps, enabling users who are blind to place a tactile printout on the pad…

Touchpad Navigation(also: Trackpad Navigation)

A method of interacting with digital content by dragging fingers or pressing specific positions on a smooth-surface touchpad input device. In accessibility contexts, touchpad navigation enables direct manipulation of spatial interfaces — such as maps or diagrams — by mapping…

Touchscreen Accessibility(also: Touch Interface Accessibility)

Touchscreen accessibility refers to the design principles, techniques, and assistive technologies that make touchscreen devices usable by people with disabilities. This includes screen reader gestures (such as VoiceOver on iOS and TalkBack on Android), which allow blind users to…

Touchscreen Exploration(also: Touch Exploration, Direct Touch Exploration)

An accessibility interaction mode where blind and low vision users explore digital content by moving their finger across a touchscreen, receiving audio or haptic feedback about elements beneath their fingertip. Touchscreen exploration has been applied to 2-D interfaces (through…

Trackball

A trackball is a pointing device consisting of a ball housed in a stationary socket that the user rotates to move the on-screen cursor, with buttons nearby for clicking. Unlike a mouse, a trackball does not require arm movement across a surface, making it valuable for people…

Trajectory Analysis(also: Route Analysis, Path Analysis)

The computational study of movement patterns over time and space, typically derived from GPS or other location data. Trajectory analysis involves modelling, comparing, and classifying sequences of spatial positions to identify patterns, anomalies, or behaviours. In assistive…

Trajectory Playback(also: Haptic Playback, Force-Guided Movement)

A technique in haptic interfaces where a force-feedback device physically guides a user's hand through a predefined path or shape. The system applies forces to move the user along a trajectory, allowing them to perceive spatial information through proprioception and kinesthetic…

Transcoding(also: 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 detecting visual layout semantics like grid structures and converting them into…

Transcription(also: Speech-to-Text Transcription, Real-Time Transcription)

The process of converting spoken language into written text, either in real time or after the fact. In accessibility contexts, transcription services provide communication access for deaf and hard of hearing individuals by producing text versions of spoken content in classrooms,…

Transfer Function(also: Mapping Function, Control-Display Gain)

A mathematical function that defines the relationship between an input signal and an output response in a control system. In assistive technology and pointer control, a transfer function determines how physical movements (such as head movements, eye gaze, or joystick input) are…

Transformation Proxy(also: Transcoding Proxy, Web Accessibility Proxy)

A transformation proxy is an intermediary server that sits between a user and the web, intercepting web pages and modifying their content before delivering them to the user's browser. In accessibility contexts, transformation proxies are used to improve the accessibility of web…

Transparent Video Overlay(also: Transparent Video, Video Overlay, Translucent Video)

A display technique where a live video feed is rendered as a semi-transparent layer on top of another application, allowing users to see both the video content and the underlying application simultaneously. In accessibility contexts, transparent video overlays have been used to…

Trimodal Feedback(also: Triple-Modality Feedback)

A form of interface feedback that delivers information through three simultaneous sensory channels — typically auditory, haptic, and visual. Trimodal feedback offers the highest level of redundancy in multimodal interface design, ensuring that users can perceive system responses…

Turn-by-turn navigation(also: 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-turn systems typically use audio cues or speech instructions to indicate when…

Tutoring System(also: Intelligent Tutoring System, ITS, Computer-Based Tutor)

Software that provides personalised instruction and feedback to learners, adapting its responses based on the learner's performance, knowledge level, and error patterns. In accessibility contexts, tutoring systems can be designed to support learners with disabilities by…

Two-Point Discrimination(also: 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 higher sensitivity. The fingertips have the highest two-point discrimination…