Glossary
Searchable terminology from accessibility, web standards, and related fields.
87 results found in visual impairment.
- Egocentric Spatial Reasoning (First-Person Spatial Understanding, User-Relative Spatial Reasoning)
- The ability of a system to understand and describe the spatial positions of objects relative to the user's body and perspective, rather than from a bird's-eye or absolute reference frame. For AI syste…
- Expanded Core Curriculum (ECC)
- A specialized curriculum for blind or visually impaired (BVI) students that supplements traditional academics with skills that sighted students typically learn through observation. The ECC covers nine…
- Eyes-free interaction (Eyes-free interface, Non-visual interaction)
- An interaction paradigm in which users operate technology without relying on visual feedback, instead receiving information through auditory, haptic, or other non-visual channels. Eyes-free interfaces…
- Frequency mapping (Pitch mapping, Frequency-position mapping)
- A sonification technique that encodes spatial position or data values as changes in audio frequency (pitch), creating an intuitive correspondence between vertical position and pitch height — low posit…
- Gesture sonification (Touch sonification, Gesture-to-sound mapping)
- The technique of converting touchscreen finger movements into real-time audio representations by mapping spatial position to sound parameters — typically pitch for vertical position and stereo panning…
- Grade 1 Braille (Uncontracted Braille, Alphabetic Braille)
- The basic level of braille in which each letter, number, and punctuation mark is represented by its own distinct braille cell, with no abbreviations or contractions. Grade 1 braille is typically used …
- Grade 2 Braille (Contracted Braille)
- The standard form of braille used in most published materials, which employs contractions — single braille characters or short groups of characters that represent common words, letter combinations, or…
- Graphic Accessibility (Image Accessibility, Visual Content Accessibility)
- The practice of making graphical content — including charts, diagrams, maps, photographs, and illustrations — perceivable and understandable by people who cannot see them. Graphic accessibility encomp…
- Guide Runner (Sighted Guide Runner, Running Guide)
- A sighted person who accompanies a blind or visually impaired runner during training or competition, providing verbal navigation cues and physical guidance typically through a tether connecting the tw…
- Guide-by-Pointing (Point-and-Ask, Hand-Guided Visual Query)
- A prompting technique for multimodal AI assistants where a user extends their hand into the camera's field of view and asks the AI to identify what they are pointing at, or to provide spatial directio…
- Hand-Over-Hand Technique (Hand-Over-Hand Guidance, Hand-Over-Hand Training)
- A training and communication method commonly used with individuals who are blind or have visual impairments, where a trainer places their hands over the learner's hands to physically guide them throug…
- Hand-Under-Hand Technique (Hand-Under-Hand Guidance, Hand-Under-Hand Training)
- A training and communication method used with individuals who are blind or have visual impairments, where the learner places their hands on top of the trainer's hands to feel the movements being demon…
- Image sonification (Visual-to-audio mapping, Auditory image display)
- The process of converting visual information from images — such as shapes, charts, diagrams, or spatial layouts — into audio representations that can be perceived without vision. Image sonification ma…
- Just-in-Time Prompting (Trigger-Based Prompting, On-Demand Visual Check)
- A prompting technique for voice and video-capable AI models where the user pre-configures the AI with a role and task description, then uses a trigger phrase (such as "check now") to initiate an on-de…
- Kurzweil Reading Machine (KRM, Kurzweil Reader)
- A pioneering reading device for blind people invented by Ray Kurzweil in 1976, combining optical character recognition (OCR) with text-to-speech synthesis to read printed text aloud. The original devi…
- Late Blind (Adventitiously Blind, Acquired Blindness)
- A person who lost their vision later in life, typically after age 5-7 when visual memories and concepts have been established. Late blind individuals often retain visual memories and may use these to …
- Legal Blindness (Legally Blind)
- A level of vision loss defined in many countries as visual acuity of 20/200 or less in the better eye with best correction, or a visual field of 20 degrees or less. Legal blindness does not necessaril…
- Line Chart Accessibility (Accessible Line Graphs, Chart Accessibility)
- The practice of making line charts and graphs perceivable and understandable by people with visual impairments through alternative representations such as tactile graphics, sonification, speech descri…
- Lookout (Google Lookout)
- An Android accessibility application developed by Google that uses the smartphone camera and machine learning to identify objects, read text, scan documents, and describe surroundings for blind and pa…
- Macular Dystrophy (Macular Degeneration)
- A group of inherited eye conditions that cause progressive damage to the macula, the central part of the retina responsible for sharp, detailed vision. Macular dystrophies, including Stargardt disease…