Glossary
Searchable terminology from accessibility, web standards, and related fields.
50 results found in usability.
- AI transparency (Algorithmic transparency, Model transparency)
- The practice of making artificial intelligence systems understandable to users and stakeholders, including how they work, what data they use, and the confidence levels of their outputs. For assistive …
- Accessibility Feature Discovery (Feature Discoverability, Accessibility Settings Discovery)
- The process by which users become aware of, find, understand, and adopt accessibility features and settings available on their devices or in software. Research consistently shows that many users who c…
- Cognitive Load (Mental Load, Cognitive Demand)
- The total amount of mental effort required to complete a task, encompassing the processing, storage, and management of information in working memory. Cognitive load theory distinguishes between intrin…
- Cognitive Walkthrough (Expert Walkthrough)
- An accessibility and usability evaluation method in which one or more experts step through a series of tasks from the perspective of a target user, identifying potential barriers and difficulties at e…
- Content Filtering (Content Adaptation, Adaptive Content Delivery)
- The process of selectively displaying or hiding portions of digital content based on user preferences, roles, device capabilities, or accessibility needs. In an accessibility context, content filterin…
- Context of Use (Use Context, Usage Context)
- The combination of users, tasks, equipment (hardware, software, and materials), and the physical and social environments in which a product or service is used. In accessibility, context of use is a cr…
- Cursor Ambiguity (Cursor Position Ambiguity)
- The difficulty users experience in determining the exact position of the text cursor, particularly when using screen readers on touchscreen devices. Screen readers announce the character or word at th…
- Customization Paradox (Paradox of Choice in Customization)
- The phenomenon where providing more customization options to reduce barriers paradoxically creates new barriers through increased cognitive load, decision fatigue, and distraction from the customizati…
- Decision Fatigue (Choice Overload, Decision Exhaustion)
- The deteriorating quality of decisions made by an individual after a long session of decision-making, or when confronted with too many choices simultaneously. Decision fatigue disproportionately affec…
- Ecological validity (Real-world validity)
- The degree to which research findings from controlled laboratory settings accurately reflect behaviour and performance in real-world everyday contexts. In accessibility research, ecological validity i…
- Error correction strategy (Text correction, Input error recovery)
- The methods and behaviours users employ to detect and fix errors during text input, including backspace deletion, cursor repositioning, autocorrect, and retyping. For blind and visually impaired users…
- Fitts' Law (Fitts Law)
- A predictive model of human movement in human-computer interaction that states the time required to move to a target area is a function of the distance to the target and the size of the target. Specif…
- Fitts's Law (Fitts Law)
- A predictive model of human movement that describes the time required to rapidly move to a target area as a function of the distance to the target and the size of the target. Formulated by Paul Fitts …
- Fitts's Law (Fitts Law, Fitts' Law)
- A predictive model of human movement that describes the time required to rapidly move to a target area as a function of the distance to the target and the target's size. Smaller and more distant targe…
- Formative Evaluation (Formative Usability Testing, Formative Assessment)
- Usability evaluation conducted early in the design process using prototypes, mockups, or wireframes to identify design problems and inform improvements. Formative testing is qualitative and iterative,…
- GOMS (Goals, Operators, Methods, and Selection rules, KLM, Keystroke-Level Model, CPM-GOMS, CMN-GOMS)
- A family of human-computer interaction models used to predict how long it will take a user to complete a task with a given interface. GOMS stands for Goals, Operators, Methods, and Selection rules — t…
- Gesture vocabulary (Gesture set, Interaction gesture repertoire)
- The complete set of touch gestures recognized and used by a device or application, including single-stroke gestures (swipes, flicks), multistroke gestures (multi-tap, draw-then-tap), and multitouch ge…
- Information Transfer Rate (ITR, Data Transfer Rate)
- A measure of the speed and accuracy with which a user can communicate information to a computer through an input device, typically expressed in bits per second. Information transfer rate accounts for …
- Input Exertion (Input Effort, Interaction Cost)
- The physical and cognitive effort required to provide input to a digital system, including keystrokes, mouse movements, taps, and voice commands. For people with motor impairments, input exertion is a…
- Keystroke-Level Model (KLM)
- A simplified predictive model from human-computer interaction research, originally developed by Card, Moran, and Newell, that estimates task completion time by decomposing user interactions into eleme…