- Published
- 8 October 2026
- Last reviewed
- 8 October 2026
How to use this glossary
Use this glossary when discussing a product idea or reviewing a digital experience. Accessibility and usability overlap but have different focuses. A glossary or first review does not establish full accessibility conformance.
Browse the alphabetical term index below. Select a term to jump to its definition, example and common mistake. Use the return link after each entry to browse again. You can also use your browser’s Find command to locate a word on this page. Definitions are original RDE plain-language explanations. All examples are fictional teaching scenarios.
Term index
12 terms, listed alphabetically.
- Accessibility
- Alternative text
- Contrast
- Focus indicator
- Hypothesis
- Information architecture
- Prototype
- Usability
- Usability testing
- User journey
- User need
- Wireframe
Definitions and practical examples
Accessibility
Meaning: Designing products and services so that disabled people can use them.
Example: A form supports keyboard operation and provides meaningful labels for its controls.
Common mistake to avoid: One passing check does not establish accessibility for every user or full WCAG conformance.
Alternative text
Meaning: A text alternative conveying an image’s relevant information or purpose.
Example: A diagram’s alternative text explains the decision sequence needed to understand the page.
Common mistake to avoid: Decorative images usually need an empty alternative; do not repeat irrelevant visual detail.
Contrast
Meaning: The difference in visual brightness or colour between elements.
Example: A designer checks whether text can be distinguished from its background.
Common mistake to avoid: Use applicable contrast criteria; visual preference alone does not establish sufficient contrast.
Focus indicator
Meaning: A visible sign showing which interface element currently has keyboard focus.
Example: A clear outline marks the link reached by pressing Tab.
Common mistake to avoid: Do not remove the indicator without providing an effective replacement.
Hypothesis
Meaning: A testable explanation or prediction about a design or user behaviour.
Example: A team predicts that clearer confirmation wording will reduce repeated submissions.
Common mistake to avoid: State how evidence could support or challenge the prediction.
Information architecture
Meaning: The organisation and labelling of information to support finding and understanding it.
Example: A resource library groups related materials and uses clear category names.
Common mistake to avoid: A neat structure for its creators may still confuse its readers.
Prototype
Meaning: A representation of a proposed design used to explore or test an idea.
Example: A clickable mock-up allows a participant to attempt a booking task.
Common mistake to avoid: A prototype can be useful without being production-ready software.
Usability
Meaning: How effectively, efficiently and satisfactorily specified users can achieve goals in context.
Example: Participants attempt a booking task and the team observes completion and difficulties.
Common mistake to avoid: A quick opinion survey is not the same as observing task performance.
Usability testing
Meaning: Observing people attempting realistic tasks with a product or prototype.
Example: A participant tries to find and book a course while a researcher records difficulties.
Common mistake to avoid: Avoid teaching the route during the task unless the research method requires intervention.
User journey
Meaning: A representation of the steps and experiences involved in pursuing a goal.
Example: A journey follows a learner from discovering a course to receiving a booking confirmation.
Common mistake to avoid: Include relevant offline and support steps rather than only the website screens.
User need
Meaning: Something a person must be able to achieve in a particular context.
Example: A learner needs to know whether a booking request has been received.
Common mistake to avoid: A request for a specific button is a proposed solution, not necessarily the underlying need.
Wireframe
Meaning: A simplified layout showing content structure and interaction placement.
Example: A low-detail page sketch identifies headings, fields and a confirmation area.
Common mistake to avoid: A wireframe does not by itself establish accessibility or validate the user journey.
A distinction worth keeping clear
A prototype makes an idea testable. A usability test observes people attempting tasks with a design. A finding describes what the evidence supports. None of these automatically demonstrates that every user need has been met.
Practise using the terms
A participant uses a paper booking prototype and cannot identify the confirmation step. Write one observation and one design hypothesis. Explain what should happen before treating the hypothesis as established. Write your answer in your own notes before reading the explanation. No answer is submitted or stored by this page.
Suggested answer and explanation
An observation could record the participant’s actions and their actual comment about the confirmation step. A hypothesis might be that the confirmation label is unclear. The team should compare observations, investigate alternative explanations and test a revised design before treating that cause as established.
Sources and scope
The sources below support the terminology and relevant context. The definitions, examples, cautions and practice tasks on this page are original RDE teaching material, not verbatim extracts or a replacement for an official standard or certification syllabus. Reviewed 8 October 2026. Author: Jefferson Otonbara Imgbi.
- W3C WAI: Accessibility, usability and inclusion
- W3C WAI: Web accessibility tutorials
- GOV.UK: User research
- W3C WAI: Understanding WCAG 2.2
Cover image: AI-generated illustrative scene created specifically for this resource.