Glossary
Searchable terminology from accessibility, web standards, and related fields.
88 results found in Accessibility Concepts.
- Recreational Exploration (Wandering exploration, Exploratory navigation, Open-ended exploration)
- Movement through an environment driven by interest, curiosity, or enjoyment rather than by a fixed destination — for example wandering a museum, browsing a shopping mall, or exploring a neighbourhood.…
- Semantic Abstraction
- The practice of defining interface elements, content, or interactions by their meaning and purpose rather than their specific visual or physical presentation. In accessibility, semantic abstraction is…
- Signifier (Perceived Affordance)
- A perceptible cue — visual, auditory, or tactile — that indicates how an element can or should be used, making an underlying affordance discoverable. In Don Norman’s refinement of affordance theory, t…
- Simultaneous Assistance
- Simultaneous assistance, described by Cynthia Bennett and Daniela Rosner, is a form of support in which help flows in multiple directions at once rather than unidirectionally from a non-disabled helpe…
- Situational Visual Impairment (SVI, Situational Visual Impairments)
- A temporary reduction in a person's effective vision or reading performance caused by the environment or context rather than by a medical condition. Common examples include trying to read a phone scre…
- Situationally-Induced Impairments and Disabilities (SIIDs, Situationally Induced Impairments and Disabilities, Situation-Induced Disabilities)
- An accessibility framework, introduced by Sears et al., that describes how everyday environments and tasks can temporarily impose the same kinds of barriers on non-disabled users that permanent impair…
- Social Play
- Social play is intrinsically motivated, voluntary activity between two or more children that has no purpose beyond itself, yet is essential to emotional, cognitive, and social development. Development…
- Speech Dialogue Design (Speech Interface Design, Auditory Dialogue Design)
- The practice of designing the structure, content, ordering, and delivery of information presented through synthetic speech in computer interfaces. Effective speech dialogue design considers psycholing…
- Speech Diversity (Diverse Speech, Non-Typical Speech)
- The full range of ways human speech varies from the narrow 'typical' speech on which most speech-AI systems are trained and benchmarked. Speech diversity includes people who stutter, d/Deaf and Hard-o…
- Standard Human Interface (SHI)
- A concept within the Pervasive Accessible Technology framework referring to a standardized set of input and output capabilities — including microphones, speakers, touch screens, glidepoint touchpads, …
- Symbiotic Learning
- Symbiotic Learning is a conceptual framing introduced by Jiang et al. (CHI 2026) describing a mode of mixed-ability family learning in which parents and children mutually enable each other's participa…
- System-Class Accessibility (Platform-Level Accessibility)
- The architectural support built into an operating system to make the entire platform usable by people with disabilities. System-class accessibility encompasses three components: alternative input and …
- Tempo (BPM, Beats Per Minute)
- The speed or pace of a musical piece, typically measured in beats per minute (BPM). Tempo is one of the primary features that shapes emotional perception of music — fast tempos (130+ BPM) are associat…
- Tree Navigation (Hierarchical Navigation, Tree View Navigation)
- The process of moving through and exploring hierarchical data structures (trees) such as file systems, program structures, organizational charts, or menu systems. In accessible computing, tree navigat…
- Turing Test (Imitation Game)
- The Turing Test, proposed by Alan Turing in 1950, is a thought experiment for assessing whether a machine's conversational behaviour is indistinguishable from that of a human. A human evaluator engage…
- UI Semantics (User Interface Semantics, Interface Semantics)
- The meaningful properties and roles of user interface elements that go beyond their visual appearance, including what an element does, how it can be interacted with, and its relationship to other elem…
- Universal Access Reference Model (UARM)
- A conceptual framework for understanding and addressing the full range of user needs in information and communication technology. The Universal Access Reference Model provides a structured approach to…
- Universal Design (UD, Design for All, Inclusive Design)
- Universal Design is the design philosophy and practice of creating products, environments, and systems that are usable by all people, to the greatest extent possible, without the need for adaptation o…
- Upper Ontology (Foundation Ontology, Top-level Ontology)
- An upper ontology is a high-level, domain-independent ontology that describes very general concepts — such as 'object', 'role', 'event', 'time', or, in a web-accessibility context, generic structural …
- User Interface Management System (UIMS)
- A software framework that separates user interface presentation and interaction from application logic, allowing the interface to be designed, modified, or replaced independently of the underlying pro…