Glossary
Searchable terminology from accessibility, web standards, and related fields.
6660 terms — page 211 of 333
- POMDP (Partially Observable Markov Decision Process)
- A Partially Observable Markov Decision Process (POMDP) is a mathematical framework for modelling decision-making in situations where an agent cannot fully observe the state of its environment. In acce…
- POUR
- The four foundational principles of WCAG: Perceivable (information must be presentable to users in ways they can perceive), Operable (user interface components must be operable), Understandable (infor…
- POUR Principles (POUR, Four Principles of Accessibility)
- The four foundational principles of the Web Content Accessibility Guidelines (WCAG): Perceivable, Operable, Understandable, and Robust. Perceivable means information must be presentable in ways users …
- PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses)
- A standardized methodology and reporting guideline for conducting systematic literature reviews and meta-analyses. PRISMA provides a structured framework including a checklist and flow diagram that do…
- PRISMA-ScR (PRISMA Extension for Scoping Reviews)
- PRISMA-ScR is the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews - a 20-item checklist and flow diagram that standardises how scoping reviews are repo…
- PS5 Access Controller (PlayStation Access Controller, Access Controller)
- Sony's highly customisable controller for PlayStation 5, released in 2023 and designed for players with limited motor control. It has a flat disc layout with interchangeable button caps and analog sti…
- PTSD (Post-traumatic stress disorder, Post-traumatic stress)
- A psychiatric condition that can develop after exposure to traumatic events, characterized by intrusive memories, avoidance of trauma-related stimuli, negative changes in mood and cognition, and heigh…
- PVI (People with Visual Impairments, Person with Visual Impairment, Persons with Visual Impairments)
- An abbreviation widely used in HCI and accessibility research for "people with visual impairments," a person-first umbrella term that includes people who are blind, legally blind, or have low vision. …
- Pa11y
- An open-source automated accessibility testing tool that runs from the command line and in continuous-integration pipelines. Pa11y can drive either axe-core or HTML CodeSniffer as its underlying rule …
- Pacing Aid (Pacing System, Time Management Aid)
- An assistive technology that helps individuals with cognitive impairments manage the timing and sequence of activities in daily routines. Pacing aids provide cues — visual, auditory, or tactile — to i…
- Packet Loss (Network Packet Loss, Data Loss)
- The failure of data packets to reach their destination during network transmission, common in VoIP and mobile telephony. Packet loss causes audio dropouts, distortion, and reduced intelligibility. Res…
- Page Fragmentation (Visual Fragmentation, Content Fragmentation)
- A web accessibility problem where different types of content on a web page (news articles, advertisements, navigation menus, related links) are visually grouped using colours, spacing, images, and lay…
- Page Landmarks (ARIA Landmarks, Landmark Regions, Landmark Roles)
- Named regions of a web page that identify its high-level structure — for example banner, navigation, main, complementary, search, form, contentinfo — so that assistive technology can expose them as ju…
- Page Linearization (Content Linearization, DOM Linearization, Source Order)
- The process by which screen readers and other assistive technologies present web page content as a sequential, one-dimensional stream of text, typically following the order of elements in the HTML sou…
- Page Magnification (Page Zoom, Web Page Magnification)
- An accessibility feature that enlarges the entire visual presentation of a web page, including text, images, and layout elements, to make content easier to see for people with low vision or visual fat…
- Page Sampling (Page Selection Strategy, Website Sampling)
- The methodology used to select which pages within a website will be evaluated during an accessibility assessment. Common strategies include evaluating only the home page, testing specific page types (…
- Page Segmentation (Web Page Segmentation, VIPS)
- The process of dividing a web page into distinct visual or structural blocks based on layout cues such as whitespace, borders, colors, and font properties. Page segmentation algorithms like Vision Bas…
- Page Structure Preservation (Layout Preservation, Structure Retention)
- The principle of maintaining the original spatial layout and DOM structure of a webpage when applying accessibility enhancements, content filtering, or other modifications. Preserving page structure e…
- Page Turner (Page Turning Aid)
- Any device, tool, or person that assists a musician in turning the pages of a music score during performance. Traditional page turners are human assistants who sit beside a musician and turn pages on …
- Pain Communication (pain expression, communicating pain)
- The verbal and non-verbal processes through which a person conveys their pain experience to others, including family members, carers, and healthcare professionals. Chronic pain presents particular com…