Definitions of accessibility terms for the web on the University of Maine System website

Whether you are new to accessibility requirements or have been working on accessibility work for a long time, having a common understanding and definition of terms can help all of us enhance our accessibility work together.

Common accessibility terms are defined below. You can find additional information and resources on the University of Maine System Information Technology (IT) Accessibility webpage.

Accessibility Terms Glossary

  • Access
  • Access barrier
  • Accessibility
  • Accessible
  • Accessible content
  • Accessible media player
  • Accommodation
  • Alternative text (“alt text”)
  • Assistive technology
  • Captions
  • Closed captions
  • Cognitive disability
  • Color blindness
  • Conformance Levels (A, AA, AAA)
  • Contrast ratio
  • Decorative image
  • Descriptive transcript
  • Disability
  • Essential
  • Images (or graphics) of text
  • Keyboard access
  • Learning disability
  • Long description
  • Reading order
  • Real time captions
  • Screen reader
  • Section 508
  • Subtitles
  • Success criteria
  • Transcript
  • Vision impairment
  • Visually customizable
  • Web Content Accessibility Guideline


The right or opportunity to use or benefit from something equally or equitably to others. In higher education, this frequently refers to the ways in which educational institutions and public policies ensure that community members, faculty, students and learners have equal access to educational opportunities and learning resources.

An obstacle to a student or learner’s access to full and equitable participation.

Elements that allow a product, service, institution or facility to be used by people with a wide range of capabilities, either directly or in conjunction with assistive technologies. The term “accessibility” most frequently addresses users who have a disability but the concept is not limited to disability issues. Examples of other issues include accessibility for users for whom English is not their first language, users with limited skills with technology such as computers or smartphones, or users who only have access to low bandwidth internet.

To be able to use something, regardless of ability.

Content that is developed specifically for websites or web applications in a way to include additional structure or information that may be used by assistive technology to improve the access to and consumption of the content for people with disabilities.

Accessible media players provide a user interface that works without the requirement of a mouse or trackpad, via a speech interface, when the page is zoomed in to be larger and with screen readers. For example, media players need to:

  • Provide keyboard support
  • Make the keyboard focus indicator visible
  • Showcase clear labels
  • Have sufficient contrast between colors for text, controls and backgrounds

Some media players provide additional accessibility functionality to users, including:

  • Changing the video speed
  • Setting how captions are displayed (e.g., text style, text size, text color and position of the captions)
  • Reading the captions with a screen reader and/or braille device
  • Interactive transcripts

An accommodation is a method outside of the parameters of Section 508 standards designed to assist users with disabilities in cases where the application of current Section 508 standards may be neither feasible nor helpful.

Text that is added to non-text content (via HTML markup), usually images such as photographs or graphics, which can be read by screen readers and other text-to-speech programs so that visually impaired and/or blind users are able to understand the purpose and function of the non-text content. Click here to read more about alt text.

Any kind of tool, equipment or product that can help a person with a disability take part successfully at school, home, work and in the community. For example, computer software and hardware, such as voice recognition applications, screen readers and screen magnifiers all can help people with mobility and sensory impairments use computer technology.

Text-based alternatives of the audio content in a video or animation which are provided to convey the information in an auditory format to users who are deaf or hard of hearing. Click here to read more about video and captions.

Captions that can be voluntarily turned on or off by the user. Click here to read more about video and captions. 

Persons with cognitive disabilities are individuals who may have difficulty with various types of mental tasks such as comprehension of acronyms or reading certain typefaces or fonts.

A reduced or lack of ability to distinguish between certain colors in combination or independently. Color blindness is usually classified as a vision disability. Click here to read more about proper color contrast ratios, which are an accommodation designed for color blindness.

Criteria by which all WCAG 2.1 and 2.0 requirements are held. Sometimes referred to as “success criteria”.

All WCAG Success Criteria are important. These are not considered “nice-to-haves” when it comes to meeting conformance. Each success criteria within the conformance levels are all accessibility requirements that should be considered mandatory for meeting in your website content. The University of Maine System website must meet Conformance Level AA requirements, per the Office of Civil Rights (OCR) Resolution.

  • Level A Success Criteria: Those which will have a high impact on a broad set of user types. This criteria usually do not focus on one type of disability only. Implementation of these requirements will typically be the easiest to achieve.
  • Level AA Success Criteria: This criteria will have a high impact for most users. Adherence to these Success Criteria have imposed logic and style requirements for the University of Maine System website. All content that lives on the System website must meet this criteria.
  • Level AAA Success Criteria: These criteria are often focused on improvements for specific user populations. These criteria can be difficult or expensive to adhere to, depending on platform limitations.

Click here to read more about WCAG. 

Contrast ratio usually means the ratio between the color of text (or additional important visual information) and the color of the background, which must meet minimum ratio levels to ensure legibility for visually-impaired and/or color blind users. Click here to read more about proper color contrast ratios.

You can use this tool to test your contrast ratio (External Site).

An image that does not convey essential information or meaning to the content on a website, is used for visual decoration only and is exempt from certain accessibility guidelines such as alternative text. Click here to read more about images. 

A descriptive transcript includes audio and visual information needed to understand the content. Click here to read more about video and transcripts. 

A physical or mental condition that restricts an individual’s abilities, movements or senses as compared to the typical standards of a group or population. Disabilities can include impairments that are physical, sensory, cognitive, intellectual and include mental illnesses and various types of chronic diseases.

Context that, if removed, would fundamentally change the function or information or of the content presented. This includes information and functionality that cannot be achieved in any other way that would conform to success criteria.

Text that has been rendered in a non-text form (e.g., within a graphic or image) in order to achieve a preferred visual effect. Click here to read more about images guidelines. 

The ability to interact with a computer using a keyboard instead of a mouse. Keyboard access is important for users who have difficulties with fine motor skills or hand-eye coordination. These users may prefer to or be required to use the keyboard to navigate through content. Keyboard controls commonly include using the Tab and Arrow keys to move from element to element (e.g. hyperlinks, buttons) and Enter/Spacebar to activate them.

A condition that may lead to difficulties in acquiring knowledge and skills to the level expected of those of the same age and physical ability. Physical ability may or may not be a factor in regards to a learning disability.

A way to use an HTML attribute (shorthand “longdesc”) that enables a longer piece of alternative text to be added to a non-text element than the alt text.

The order in which a screen reader reads content that is on a page. Reading order may not be the same as visual order. The reading order is an important consideration when designing page and website navigation because screen reader users use keyboard commands to navigate around and through the content.

Real-time captions, or Computer Assisted Real-time Translation (CART), are created as an event takes place. A captioner (often trained as a court reporter or stenographer) uses a stenotype machine with a phonetic keyboard and special software. A computer translates the phonetic symbols into captions almost instantaneously and displays them on a laptop or on a large display screen. Click here to read more about video and real time captions, or visit the University of Maine System Information Technology (IT) Accessibility Live Event Captioning (CART) webpage for a list of approved live captioning partners for the University of Maine System.

An assistive technology for people with visual impairments that provides text-to-speech reading of content, speech-to-text dictation and voice control for navigating the use and interaction with a computing device.

The standards that were issued under Section 508 of the Rehabilitation Act. The standards require access for members of the public and federal employees to such technologies when developed, procured, maintained or used by federal agencies or any institution that receives federal funds.

For hearing users, subtitles provide on-screen text for videos, films and animations provided for users who do not understand the language of the dialogue being spoken in the language that they are able to read. Subtitles are different from captions, which are intended for deaf and/or hard-of-hearing users. Click here to read more about video and subtitles. 

For each guideline set by WCAG 2.1 or 2.0, success criteria is testable criteria which is provided to allow WCAG standards to be used where requirements and conformance testing are necessary. This includes design specification, purchasing, regulation and contractual agreements. In order to meet the needs of different groups that may require accommodation and different situations, three levels of conformance are defined: A (lowest), AA (middle), and AAA (highest).

Text Alternative (which is different from Alternative Text or “alt-text”) is additional text that is provided to convey the same information that is presented by non-text content (such as charts, media files, tables etc.).

Providing a text alternative also allows screen readers to convert the text into speech output for visually impaired and/or blind users. Providing the information in text also makes it possible to translate the information into braille, sign language, other languages, pictures or simpler forms of writing.

A text-based alternative, often on a webpage, to audio/video content that enables deaf and/or hard-of-hearing users to access the content. Click here to read more about video and transcripts. 

Visual impairments may include blindness or low vision. Vision impairment does not necessarily refer to limited distance vision. Low vision applies to all individuals with sight who are unable to read at a typical viewing distance for their age or otherwise physical ability, which is unable to be improved with corrective lenses or surgery.

Click here to read more about proper color contrast ratios, which are an accommodation designed for color blindness and low vision.

Meaning that the font size, font color and background colors can be set in a customized way.

Often referring to Web Content Accessibility Guidelines version 2.0 and 2.1, but soon to include and be changed to 3.0. These are a set of internationally-agreed recommendations and success criteria developed by the World Wide Web Consortium (W3C) to make web content more accessible for users with disabilities. The University of Maine System website is required to follow WCAG 2.0 AA guidelines per the Office of Civil Rights (OCR) Resolution.