Glossary of terms

Glossary of frequently used terms and abbreviations

We know that in digital media, specifically web-development and digital accessibility there are many acronyms and terms that may be new to our users, we aim to help our users understand them by providing definitions, all in one place.

3rd party

A 3rd party usually means a person or organisation that is not necessarily a primary stakeholder in a project, as they do not need to play a significant part. An example could be a contract between a buyer and a reseller of some software, the contract is between the buyer and seller and the 3rd party is the software developers, if the software solution is exactly what the buyer needs, they may never need to speak to the 3rd party


Accessibility Object Model, (often called the Accessibility Tree) the parts of HTML and ARIA that are understood by assistive technologies


Application Programming Interface, is a way that computer programs communicate with each other, an example could be if you were to download a receipt from an email to store in your documents folder, the email client would use an API to access your computer's filesystem, so it can actually store the file on your device, in accessibility, a browser needs access to the operating system's accessibility API, so it can pass that information to assistive technologies


Accessible Rich Internet Applications, attributes that can add names, roles, and states to HTML elements or widgets, to assist Assitive Technologies to better convey the element or widget's purpose, current state or how to interact with it


Assistive Technologies, screen readers, magnifiers, switch inputs, voice inputs and other pieces of hardware or software that assist users in accessing web pages or computers


For the anti-overlay folks amongst us, this is a browser plugin that blocks most of these overlays before they have chance to modify a page with their solutions that many experts have demonstrated are not solutions at all

Accessibility statement

An accessibility statement is a specific legal document that organisations must publish under the Public Sector Bodies Accessibility Regulations (PSBAR). The statement must include information about accessibility issues on a system, contact information, enforcement procedure, as well as several other legally required sections. There is a specific template in the UK that must be followed for accessibility statements under PSBAR. Private companies or others not covered by PSBAR may choose to write an accessibility statement. A good statement will still be similar to a PSBAR statement in terms of listing issues, contact information etc. but does not require certain pieces of legal wording.


An expandable widget or component, typically a large button with some text inside it and some identifier such as an arrow or plus icon etc, which when clicked reveals a panel containing some content. An accordion uses the Basic Disclosure pattern, which in essence expands or collapses after clicking the trigger element (the button)

Alt format

An alternative (alt) format means content provided through different means. Many disabled users may have trouble accessing content in its original format and request an alt format. For example, a blind user may have trouble using a PDF scan of a document because that PDF is an image produced by a scanner, not text in a document. That user may ask for a computer readable alternative, such as the text in a Microsoft Word document, so that it can be read out by the user's screen reader. There are legal requirements in the UK around providing reasonable alternative formats when asked to do so.

Alt text

Alternative (Alt) text descriptions, alt-tags (they're often incorrectly called alt tags, they're attributes) or alt-attributes are phrases used to describe text which is associated with an image. This text is used to describe the image for blind users and should be only a couple of sentences that describes the image in the context it is being shown.

Arc Toolkit

Is an automated tool created By TPGi (formerly The Paciello Group), it runs a set of tests against a page, helping a user to identify many accessibility issues

Automated accessibility checkers

Both automated and semi-automated accessibility checkers are software solutions that can analyse single pages (semi-automated) or whole sites (automated) for a range of accessibility issues. Semi-automated tools typically require a user to run the tool against a page, whereas automated tools can be scheduled to test entire sites. Both have limitations in what they can actually detect, due to the need for manual reviewing of many accessibility issues


A semi-automated accessibility tool that is typically installed as an extension on a browser and enables a user to detect a range of accessibility issues


A bookmarklet is a small script that can be saved into the bookmarks bar of a browser, then ran once clicked. There's a large amount of these out there, many of which are awesome for testing against certain accessibility issues, such as valid HTML, text resizing and much more


Commercial-off-the-shelf, typically a hardware a software solution which is commercially available and not developed especially for the buyer. If a buyer wanted some text editing software, for their company to write documents, they would likely purchase a productivity suite, for office type applications


Cascading Style Sheets, the styling language on webpages that is responsible for colours, layouts and all other visual aspects of the page


The screen reader pre-installed on ChromeBooks

Colour contrast

The difference in colour between 2 or more colours. Typically in web accessibility this relates to the background colour and the foreground colour, the background would be any colour directly underneath text, icons or controls etc and the foreground colour would be the text, control or icon etc. This is especially important, as very low contrast makes things harder to read or perceive for a large amount of users


When we say content we are referring to anything that is user generated for example the text and images that goes into a web article, documents or other user generated material.


Document Object Model, The structural representation of a webpage, which allows access to other technologies to manipulate it, enhance it or parse (read) it

Decorative image

Some images are described as "decorative" in that they do not show any important information relevant to the context of the discussion. For example, a decorative image may be a nice picture in a powerpoint used, to fill space and "look nice" but not add any important information to the discussion. Decorative images have a "NULL" or blank alt text, or are specifically marked as decorative in document formats.

Developer Tools

The developer tools are a combination of tools available to inspect a website's source code and all frontend assets. Typically, the "dev tools" is a panel that opens within the browser and is accessed by right-clicking anywhere on a page and choosing "Inspect Element" (or similar wording) or by pressing F12. Within the Dev Tools, we can see all of the page's HTML, CSS and JavaScript and we can access accessibility information about the page, tools in various browsers have different options, so it's useful to use them in multiple browsers

Digital Inclusion

Digital inclusion is often associated with accessibility, but digital inclusion is a different but related topic. Digital inclusion encompasses things like users' digital literacy (their familiarity with computers and the web), access to a computer, socio-economic background, English not being a user's first language and many other factors. The purpose of which is to get us to think about our content and how we engage with these users in a world where "online" is the first route for most things.

Digital Literacy

Digital literacy refers to user's familiarity and confidence with computers and the internet. For example someone that has spent a lot of time on the internet and is capable of independently using a computer to achieve most tasks is considered digitally literate. On the other hand, someone who may not have had much interaction with computers due to age, economic circumstances, or other factors, may not be familiar with controls or navigating a computer or website, and may not be able to complete tasks by themselves. This kind of user would be less digitally literate depending on how much help they need.

Disproportionate Burden

Claiming disproportionate burden is a mechanism within the Public Sector Bodies Accessibility Regulations (PSBAR) for organisations to explain why meeting a very specific part of the regulations in a single case is not feasible at this time. Claiming disproportionate burden requires significant evidence of financial, time, resources and other impacts among other things and must show it is not substantially impacting disabled users of a system. An organisation can only claim disproportionate burden after an assessment has been completed.


Dragon Naturally Speaking, Voice input software that enables users to control computers with their voice


The Equality Advisory and Support Service (EASS) for part of the monitoring process for the Public Sector Bodies Accessibility Regulations (PSBAR). If you have a PSBAR complaint about the accessibility of a website, you should make the complaint to the EASS who will offer you advice to help resolve the issue, and pass the complaint on for further monitoring under the regulations.


The Equality Commission of Northern Ireland (ECNI) are responsible for enforcing the Public Sector Bodies Accessibility Regulations (PSBAR). Because the ECNI is responsible for enforcing the Disability Discrimination Act 1995, which underpins PSBAR, the ECNI are also responsible for enforcing PSBAR within Northern Ireland.


Equality, Diversity, and Inclusion (EDI) is an umbrella term covering a wide variety of action aimed at advancing fair and equal treatment, representation and engagement of minority groups. This includes action to support disabled people. Accessibility work is often considered to contribute to EDI objectives as practical steps to offering a more inclusive environment.


The Equality and Human Rights Commission (EHRC) are responsible for enforcing the Public Sector Bodies Accessibility Regulations (PSBAR). Because the EHRC is responsible for enforcing the Equality Act 2010, which underpins PSBAR, the EHRC are also responsible for enforcing PSBAR within Great Britain.

Ease of Access Centre

The accessibility settings on Windows operating systems. This is where users will find system-wide controls to help them to access software, applications and websites in ways that meet their individual requirements. For example, the settings to quickly turn on the Narrator screen reader of voice dictation are in there, along with many other options

Easy Read

Easy Read content is a specific type of alternative format aimed at an audience with cognitive disabilities or other trouble easily understanding complex topics. Easy read content often breaks down complex topics into several points each accompanied by an associated image.
Easy read content is not the same as "plain English" which is an approach to making content clearer and easier to understand by a general audience.


An Equality Impact Assessment (EqIA) is a review activity and associated documentation which are tools used to review the impact of any decisions on user groups who for example might fall within one of the protected characteristics of the Equality Act such as having a disability. Most organisations have their own processes and templates for these assessments and you should contact HR or EDI colleagues for direction.

Expandable content

Content which may initially be hidden from view, when its trigger element (a button) is clicked, some additional content is displayed. this could be an accordion ora mobile navigation's site links, for example


An "extranet" is a term for a semi-open type of digital system. Intranets are available only for staff, and public facing systems are available to everyone. Extranets are managed systems that are open to select groups which may contain staff of your organisations, staff from other organisations, or members etc. Some public facing websites might have members sections or areas that a user can "login" to, which would be classed as an extranet. Another example of an extranet would be student systems for a university. These systems are not open to everyone, but are available to a wide customer base beyond just university employed staff.


The Government Digital Service (GDS) are a government body and part of the UK Cabinet office. GDS are the monitoring body for the Public Sector Bodies Accessibility Regulations (PSBAR) and hold responsibility for checking the compliance of organisations.

H1 - H6

Headings on a web page, A H1 should ordinarily be the primary page heading, sections should have H2s, subsections should have H3s and so forth


HyperText Markup Language (the code that forms the structure and content of a web page, tags which are always contained in angle brackets <>)

Headings Map

A browser plugin that can display the page's heading hierarchy, to assist a user in identifying whether the correct structure for headings has been used and if headings are marked up with the appropriate tags, as opposed to them being styled to look like headings and vice versa

IBM Equal Access Accessibility Checker

An automated tool that tests a site on a per-page basis, for many accessibility issues. The whole suite also includes tools for checking desktop and mobile applications, in addition to websites

Interactive element

An interactive element is part of a web page, app or system that a user can interact with and it "does something". For example, links and buttons are interactive as clicking a link takes you to a new page, and clicking a button does something on the current page. In contrast, static elements such as text and often images provide information but cannot receive action back from a user.


There are two definitions for "intranets".
The first is the term for a specific type of internal facing company system that normally serves as a central place for important organisational material, such as links through to HR and IT services, policy information, organisational news and other internal content. The second is within the public sector bodies accessibility regulations (PSBAR) where "intranet" refers to ANY internal facing system that only organisation staff use.


Job Access With Speech, A screen reader available to purchase for Windows machines


JavaScript, the scripting language (code) that can make web pages interactive and manipulate other technologies such as ARIA, CSS & HTML etc

Keyboard navigable

Software, applications or websites that allow users to navigate the interface with a keyboard, as opposed to a mouse or touchscreen, this behaviour is in fact the default behaviour of websites, but all too often, some folk over engineer things and don't consider people that access interfaces in ways different to them


Lighthouse is built into the Dev tools in Chromium-based browsers (Chrome, Edge, Brave etc) and can analyse a page to give it scores on several categories, such as accessibility, SEO (Search Engine Optimisation), performance, progressive web app, and best practices. the accessibility tool uses AXE, although it is not as fully featured as the full AXE plugin


A screen magnifier is an assistive technology which typically enlarges all or part of a screen, a user who has low-vision may use a magnifier to display text and controls much larger than would be possible using the browser's inbuilt zoom functionality. It acts like a digital magnifying glass, in that a user would move it around with their mouse and be able to see the content more clearly

Manual testing

The technique of a person or persons who are typically familiar with web accessibility standards and practices, performing a technical audit against a website or application, to identify any accessibility issues. Many of the tests performed will will be conducted using various tools and techniques, including but not limited to: Assistive technologies, zooming and resizing the browser, user flows, colour contrast, keyboard testing, validating alt text and much more

Microsoft Accessibility Insights

A semi automated tool which can help identify many accessibility issues on a per-page basis. The tool can run a 1 page automated scan or it can run guided tests, where a user is required to confirm certain behaviours have taken place, such as keyboard focus returning back to the correct button upon closing a disclosure widget and many more


Non-Visual Desktop Assistant, a screen reader available to download for free on Windows machines


The screen reader pre-installed on Windows machines

Non-pointing device

Keyboards, voice input software, sip and puff devices, mouth sticks, switches, foot pedals and other hardware or software that allows users to interact with computers without the requirement for identifying and pointing at controls


A screen reader free to install on Linux operating systems


Overlays hate them or not (why not?) have come to the fore in recent years. These are tools that are added to a site usually with a line of JavaScript which calls an API from the overlay vendor. The vendors claim that their tool can magically fix an inaccessible site and suddenly make it accessible. These tools are not well accepted in the digital accessibility community, as many world-renowned specialists and end users have found the claims to be wide of the mark, citing that they do not in fact make sites accessible at all. Here at Make Things Accessible, we agree with the findings of experts and promote considering all users throughout every stage of the project's lifecycle


Portable Document Format, a common file type for text and/or image-based documents


Public Sector Bodies (Websites and Mobile Applications) (No. 2) Accessibility Regulations 2018. The legislation that requires UK public sector bodies, higher and further education and some other organisations to ensure their websites and apps meet the required standard

Plain English

Plain English is a term used to describe the process of improving content to be easily understood by the intended users. This includes techniques to simplify language, increase the clarity of statements, cut out padding words and even consider aspects such as layout when trying to make content as easy to understand as possible.
Plain English is different to "Easy Read" which is a specific alternative format.

Pointing device

A mouse, trackpad, finger on a touch screen, stylus, laser pens and other input devices that allow users to interact with using point and touch or click based gestures

Public Facing

The term "public facing" is used to describe a type of digital system which is available to the general public. Most websites that can be accessed online fall within this category. Some public facing websites might have members sections or areas that a user can "login" to, which would be classed as an extranet area.

Public Sector

The definition for "public sector" within the Public Sector Bodies Accessibility Regulations (PSBAR) is broad. Some organisations such as local government or NHS hospitals are public services and are clearly public sector. The regulations extends the definition to cover any organisation that is more than 50% funded or managed by other public sector bodies. For instance, universities that receive the majority of their funding through student loans from the government are classified as public sector in this specific context. This could also apply to local authority trading companies which are commercial branches of local government entities and are often majority managed by those local government public sector bodies.

Screen reader

A piece of software that is able to understand the structure and content of operating systems, applications or webpages and relay that information back to a user in a digitised voice or braille. Typically used by, but not limited to blind or low-vision people, as other indiduals can also benefit from having content read out to them


When we say systems we are referring to a wide range of digital products which includes; any browser based platform (website, intranets), mobile applications, and other web content (plugins, chatbots, overlays). Systems may be built in house or purchased from 3rd parties. They may be customised to you, bespoke, or a generic service you subscribe to. This definition is used when discussing generic behaviour, such as asking for accessibility requirements in procurement regardless of the type of system. Where guidance applies to specific system types, more detail will be given.

Tabbed Interface

Not to be confused with navigating with the 'tab' key. A tabbed interface is a widget or component that has multiple 'tabs', each tab when currently selected will display the contents of that particular tab (Think dividers in a ring binder, where the labels of each divider are typically positioned in such a way that they do not overlap one another, allowing a person to quickly open the folder at the correct index or document)


"Tabbing" refers to the control by which keyboard and screen reader users move through interactive elements of a web page, app or system. These users press the tab key to move through all interactive elements and there are other controls for moving through just links or buttons etc. When a report says that an element could not be tabbed to, or you can't get to it by tabbing, it means that a user that is "tabbing" cannot get to that element through the common keyboard controls.


The screen reader pre-installed on Android phones and tablets


Virtual Product Accessibility Templates (VPATs) are a templated document required by the American Section 508 legal requirements. They include a WCAG 2.0 or later version checklist, functional criteria for use with various limitations or disabilities, hardware compliances, and support documentation requirements. VPATs are a common piece of evidence used internationally to demonstrate accessibility testing and compliance.

Voice input

Software that allows users to control computers using their voice, a user may command the software to click the "home" link and the software can then click the correct link on a page (assuming the page is marked up correctly and links are unique)


VoiceOver, the screen reader pre-installed on Apple devices including iPhones and iPads


Web Accessibility Evaluation Tool is a browser plugin developed by WebAIM and is a semi-automated accessibility testing tool. WAVE can help developers, content editors and other stakeholders identify a range of accessibility issues on a per-page basis, testing for invalid code, missing roles or attributes, colour contrast and much more


Web Content Accessibility Guidelines (The technical specification that lists required testable criteria and advisory best practices to make websites more accessible to users). The minimum legal requirement in the UK for the publically funded bodies is Level AA against the WCAG 2.1 specification


Windows High Contrast Mode, a user setting on Windows which enforces the system to display screens in very high contrast, such as white text on black backgrounds, or indeed any theme a user chooses, which could also be a low-contrast theme

WebAIM Contrast Checker

A tool used to analyse the contrast between a foreground element and its background, simply by pasting in the hex codes of each colour. This tool is very useful for determining whether an element has sufficient contrast.

Zoom Text

A paid for screen magnifier, that enables users to magnify and enhance content on a page to extremely high levels of zoom, the software is developed by Freedom Scientific, who also created the JAWS screen reader