Glossary

Searchable terminology from accessibility, web standards, and related fields.

50 results found in usability.

Learnability
A usability attribute measuring how easy it is for users to accomplish basic tasks the first time they encounter a design. High learnability means new users can quickly become productive with a system…
Material Experience (Material Aesthetics, Material Interaction)
The multidimensional way people perceive, interpret, and emotionally respond to the physical materials of objects they interact with. The materials experience framework categorizes these experiences i…
Mental Fatigue (Cognitive Fatigue, Mental Exhaustion)
A state of reduced cognitive capacity resulting from prolonged mental effort, characterized by difficulty concentrating, slower processing, increased errors, and reduced ability to handle unexpected s…
Midas Touch Effect (Midas Touch Problem)
An interaction design challenge in touch-based and gesture-based interfaces where the system cannot distinguish between intentional activation commands and incidental or exploratory touches. Named aft…
NASA Task Load Index (NASA-TLX, Task Load Index)
A widely used subjective workload assessment tool developed by NASA that measures perceived workload across six dimensions: mental demand, physical demand, temporal demand, performance, effort, and fr…
NASA Task Load Index (NASA-TLX, TLX)
A widely used subjective workload assessment tool developed by NASA that measures perceived workload across six dimensions: mental demand, physical demand, temporal demand, performance, effort, and fr…
NGOMSL (Natural GOMS Language)
A structured notation for writing GOMS (Goals, Operators, Methods, Selection rules) models in a program-like form that is readable by humans. NGOMSL was developed by David Kieras as a more formal vari…
Procedural task analysis (Task decomposition, Step-by-step analysis)
A method of breaking down complex tasks into sequential, discrete steps to understand user workflows and identify points of difficulty. In accessibility contexts, procedural task analysis reveals wher…
Progressive Disclosure (Staged Disclosure, Layered Interface)
An interaction design pattern that initially presents only the most essential options or information, revealing additional complexity progressively as users need or request it. Progressive disclosure …
SUMI (Software Usability Measurement Inventory)
A standardised questionnaire-based method for measuring software usability from the end user perspective. SUMI assesses five dimensions: efficiency, affect (user satisfaction), helpfulness, control, a…
SUS (System Usability Scale)
Abbreviation for System Usability Scale, a ten-item questionnaire developed by John Brooke in 1986 that produces a single usability score from 0 to 100 based on user ratings of agreement with statemen…
Social Acceptability (Social Acceptance, Technology Stigma)
The degree to which the use of an assistive technology or interaction technique is perceived as socially appropriate by both the user and those around them. Social acceptability is a critical but ofte…
Social usability
The degree to which a technology supports positive social interactions and self-presentation for its users, particularly in contexts where technology use is visible to others. Social usability goes be…
Speech Repair (Self-Correction, Speech Self-Repair, Command Correction)
Speech repair is the process of correcting or modifying a spoken utterance after it has been produced, either within the same turn or in a subsequent one. In natural conversation, speakers commonly in…
Summative Evaluation (Summative Usability Testing, Summative Assessment)
Usability evaluation conducted on functional software or high-fidelity prototypes, typically later in the development process, to measure the effectiveness of specific design choices. Summative testin…
Task-Technology Fit (TTF)
A concept from information systems research describing how well a technology's capabilities match the requirements of the tasks it is used to perform. In assistive technology, task-technology fit is c…
Technology acceptance (User acceptance, Technology adoption)
The degree to which individuals are willing to embrace, use, and integrate a new technology into their practices, influenced by perceived usefulness, ease of use, social norms, trust, and prior experi…
Text Correction (Text Editing, Error Correction)
The process of identifying and fixing errors in text, including substituting incorrect words, inserting missing content, and deleting extraneous characters or words. For blind users, text correction o…
Think Aloud Protocol (Think-Aloud Method, Verbal Protocol Analysis, Thinking Aloud)
A usability testing method in which participants verbalize their thoughts, feelings, and decision-making processes while performing tasks with a system or interface. Developed for cognitive interface …
Think-Aloud (Think-Aloud Protocol, Verbal Protocol Analysis)
A research method in usability and accessibility testing where participants verbalize their thoughts, strategies, and reactions while performing tasks. Think-aloud protocols are particularly valuable …