W3C logoWeb Accessibility initiative

WAI: Strategies, guidelines, resources to make the Web accessible to people with disabilities

In-Suite Navigation

Diversity of Web Users
[DRAFT] How People with Disabilities Use the Web

Introduction

This page explores the wide range of diversity of people and abilities, and highlights some of the types of web accessibility barriers that people commonly encounter from poorly designed websites and web tools.

Note: This page is illustrative and is not intended to be an exhaustive listing of all disabilities and barriers.

On this page

Diversity of abilities

There are many reasons why people may be experiencing varying degrees of auditory, cognitive, neurological, physical, speech, and visual disabilities. For instance, some may have disabilities from birth, an illness, disease, or accident, or they may develop impairments with age. Some may not consider themselves to have disabilities even if they do experience such functional limitations.

More about diversity of abilities

Each individual is unique. People have diverse abilities, skills, tools, preferences, and expectations that can impact how they use the Web. For instance, consider the following aspects:

  • Age-related impairments: Many people develop age-related impairments. While they share the same functional requirements as others with disabilities, sometimes there are significant differences in the use of assistive technologies, the level of computer skills, or in the use of the Web in general.
  • Multiple disabilities: Some people have combinations of different kinds of disabilities, which may limit their approaches for interacting with the Web. For instance, someone who is deaf and has low vision might benefit from captions for audio, but only if these captions have adjustable size and color.
  • Health conditions: Some people have health conditions that may affect their stamina, dexterity, or concentration. For instance, some may experience fatigue, pain, or other symptoms that could affect their physical use of the computer or limit the duration or extent of their use of the Web.
  • Changing abilities: Some people may be experiencing progressive or recurring functional limitations that impact their use of the Web differently at different times. For instance, some may need particular accessibility features on one day, and others or none on another day, depending on their condition.
  • Temporary impairments: Some people may be experiencing temporary impairments such as those that may occur due to an accident, surgery, or medication. They may not know about accessibility solutions, may not know how to use accessibility features, and may be unaware of their own needs.
  • Situational limitations: Some people may be experiencing constraints due to their surrounding or due to other situational aspects. For instance, they may be in a loud environment and unable to hear audio, in bright sunlight and unable to see a screen, or they may not be able to afford some technologies.

Websites and web tools that are designed for people with a broad range of abilities benefit everyone, including people without disabilities. It is therefore important to consider the broad diversity of functional needs rather than to categorize people according to medical classifications.

back to page contents

Auditory

Auditory disabilities range from mild or moderate hearing impairments in one or both ears ("hard of hearing"), to substantial and uncorrectable impairment of hearing in both ears ("deafness"). Some people with auditory disabilities can hear sounds but sometimes not sufficiently to understand all speech, especially when there is background noise. This includes people using hearing aids or other approaches to improve the sound.

More about auditory disabilities

While the rapid increase of multimedia on the Web provides many new opportunities for people with auditory disabilities, it also poses challenges when content is not designed to be accessible. For instance, while video content can be used to communicate information visually, audio content needs to have alternatives, such as transcripts and captions, so that it is accessible for people with auditory disabilities.

To use the Web effectively, people with auditory disabilities need:

  • Transcripts and captions of audio content, including audio-only content and audio tracks in multimedia
  • Media players that display captions and provide options to adjust the text size and colors of captions
  • Options to stop, pause, or adjust the volume of audio content (independently of the system volume)
  • High-quality foreground audio that is clearly distinguishable from any background noise

For some people with auditory disabilities, sign language is the first language and they may not read a written language fluently. Providing important information in sign language and using simpler text that is supplemented by images, graphs, and other illustrations help make web content more understandable to many. However, it is important to remember that not all people with auditory disabilities know sign language.

Examples of auditory disabilities

  • Hard of hearing - mild or moderate hearing impairments in one or both ears
  • Deafness - substantial, uncorrectable impairment of hearing in both ears
  • Deaf-blindness - substantial, uncorrectable hearing and visual impairments

Examples of barriers for people with auditory disabilities

  • Audio content, such as videos with voices and sounds, without captions or transcripts
  • Media players that do not display captions and that do not provide volume controls
  • Media players that do not provide options to adjust the text size and colors for captions
  • Web-based services, including web applications, that rely on interaction using voice only
  • Lack of sign language to supplement important information and text that is difficult to read

Sections related to auditory disabilities

Stories of web users:

Diversity in web use:

Accessibility principles:

back to page contents

Cognitive and neurological

Cognitive and neurological disabilities involve disorders of any part of the nervous system, including the brain and the peripheral nervous system. This can impact how well people hear, move, see, speak, and understand information. Cognitive and neurological disabilities do not necessarily affect the intelligence of a person.

More about cognitive and neurological disabilities

Computer technologies and the Web provide many opportunities for people with cognitive and neurological disabilities to interact with content and to process information in ways that are more usable to them. For instance, people can navigate web content using different strategies, access information in text, audio, or other formats, and change the presentation of the content according to their individual needs or preferences.

Depending on the particular needs of an individual, people with cognitive and neurological disabilities need:

  • Clearly structured content that facilitates overview and orientation
  • Consistent labeling of forms, buttons, and other content parts
  • Predictable link targets, functionality, and overall behavior
  • Different ways of navigating websites, such as through a hierarchical menu or search option
  • Options to suppress blinking, flickering, flashing, or otherwise distracting content
  • Simpler text that is supplemented by images, graphs, and other illustrations

People with cognitive and neurological disabilities use different types of web browsing methods, depending on their particular needs. For instance, some people use text-to-speech software to hear the information while reading it visually, or use captions to read the information while hearing it. Some people use tools that resize text and spacing, and customize colors to assist reading, and grammar and spelling tools to assist writing. For these web browsing methods to work, developers need to consider web accessibility requirements which are often shared by people with hearing, physical, speech, or visual disabilities.

Examples of cognitive and neurological disabilities

  • Attention deficit hyperactivity disorder (ADHD) (formerly "attention deficit disorder (ADD)") - involves difficulty focusing on a single task, difficulty focusing for longer periods, or may be easily distracted
  • Autism spectrum disorder (ASD) (includes "autism", "Asperger syndrome", and "pervasive developmental disorder (PDD)) - involves impairments of social communication and interaction abilities, and sometimes restricted habits and interests
  • Intellectual disabilities (sometimes called "learning disabilities" in Europe and some other countries, and "developmental disabilities" in other regions) - involves impairments of intelligence, learning more slowly, or difficulty understanding complex concepts. Down syndrome is one among many different causes of intellectual disabilities
  • Learning disabilities - is a functional term rather than a medical condition, and is not uniformly defined. In Europe and some other countries it refers to intellectual disabilities, while in Australia, Canada, the U.S., and some other countries it refers to perceptual disabilities.
  • Mental health disabilities - includes anxiety, delirium, depression, paranoia, schizophrenia, and many other disorders. These conditions may cause difficulty focusing on information, processing information, or understanding it. In particular medication for these disorders may have side effects including blurred vision, hand tremors, and other impairments
  • Memory impairments - involves limited short-term memory, missing long-term memory, or limited ability to recall language. Dementia is one among many different causes of memory impairments
  • Multiple sclerosis - causes damage to nerve cells in the brain and spinal cord, and can affect auditory, cognitive, physical, or visual abilities, in particular during relapses
  • Perceptual disabilities (sometimes called "learning disabilities" in Australia, Canada, the U.S., and some other countries) - involves difficulty processing auditory, tactile, visual, or other sensory information. This can impact reading (dyslexia), writing (dysgraphia), processing numbers (dyscalculia), or spatial and temporal orientation
  • Seizure disorders - includes different types of epilepsy and migraines, which may be in reaction to visual flickering or audio signals at certain frequencies or patterns

Examples of barriers for people with cognitive and neurological disabilities

  • Complex navigation mechanisms and page layouts that are difficult to understand and use
  • Complex sentences that are difficult to read and unusual words that are difficult to understand
  • Long passages of text without images, graphs, or other illustrations to highlight the context
  • Moving, blinking, or flickering content, and background audio that cannot be turned off
  • Web browsers and media players that do not provide mechanisms to suppress animations and audio
  • Visual page designs that cannot be adapted using web browser controls or custom style sheets

Sections related to cognitive and neurological disabilities

Stories of web users:

Diversity in web use:

Accessibility principles:

back to page contents

Physical

Physical disabilities (sometimes called "motor disabilities") include weakness, limitations of muscular control (such as involuntary movements including tremors, lack of coordination, or paralysis), limitations of sensation, joint problems (such as arthritis), pain that impedes movement, or missing limbs.

More about physical disabilities

To use the Web, people with physical disabilities often use specialized hardware and software such as:

  • Ergonomic or specially designed keyboard or mouse
  • Head pointer, mouth stick, and other aids to help typing
  • On-screen keyboard with trackball, joystick, and switches to operate it
  • Voice recognition, eye tracking, and other approaches for hands-free interaction

People with physical disabilities may be using a mouse or mouse-like device only, or keyboard or keyboard-like device only to operate the computer. People with physical disabilities need full keyboard support for all functionality provided on a web page. They may need more time to type, click, or carry out other interaction, and they may type single keystrokes in sequence rather than typing simultaneous keystrokes ("chording") to activate commands. This includes commands for special characters, shortcut keys, or to active menu items.

People with physical disabilities often have trouble clicking small areas and are more likely to make mistakes in typing or clicking. Providing large clickable areas, enough time to complete tasks, and error correction options for forms are important design aspects. Other important design aspects include providing visible indicators of the current focus, and mechanisms to skip over blocks, such as over page headers or navigation bars. Many of these requirements are shared by people with cognitive, neurological, and visual disabilities.

Examples of physical disabilities

  • Amputation and deformity - includes missing fingers, limbs, or other parts of the human body
  • Arthritis (previously called "rheumatism") - inflammation, degeneration, or damage of the joints
  • Fibromyalgia (previously called "rheumatism") - chronic pain of muscle and connective tissues
  • Rheumatism - typically refers to arthritis and other causes for bone or joint pain, and sometimes to fibromyalgia and other causes for muscular and other soft tissue pain
  • Reduced dexterity - is a functional term (rather than a medical condition) that describes the ability to control the hand, such as hand-eye coordination of people with cognitive and neurological disabilities
  • Muscular dystrophy - progressive weakness and degeneration of muscles, including in arms and hands
  • Repetitive stress injury (RSI) (also called "repetitive motion disorder" (RMD) and "cumulative trauma disorder" (CT)) - involves injuries to the musculoskeletal system (bones, joints, tendons, and other connective tissues) and the nervous system from repetitive tasks and damage
  • Tremor and spasms - involuntary movement or muscle contraction, including short twitches, and continual or rhythmic muscle contractions
  • Quadriplegia (sometimes called "tetraplegia") - partial or total paralysis (includes motor control and sensation) to all four body limbs (legs and arms) and the torso

Examples of barriers for people with physical disabilities

  • Websites, web browsers, and authoring tools that do not provide full keyboard support
  • Insufficient time limits to respond or to complete tasks, such as to fill out online forms
  • Controls, including links with images of text, that do not have equivalent text alternatives
  • Missing visual and non-visual orientation cues, page structure, and other navigational aids
  • Inconsistent, unpredictable, and overly complex navigation mechanisms and page functions

Sections related to physical disabilities

Stories of web users:

Diversity in web use:

Accessibility principles:

back to page contents

Speech

Speech disabilities include difficulty producing speech that is recognizable by others or by voice recognition software. For instance, the loudness or clarity of someone's voice might be difficult to understand.

More about speech disabilities

People with speech disabilities encounter barriers with voice-based services, such as automated web-based hotlines and web applications that are operated using voice commands. To use services that rely on voice, people with speech disabilities need alternative modes for interaction such as a text-based chat to interact with hotline representatives or keyboard commands to operate web applications. Also, websites that provide telephone numbers as the only means of communicating with an organizations pose barriers for people with speech disabilities. Alternative means of communication include e-mail and feedback forms.

Examples of speech disabilities

  • Apraxia of speech (AOS) - includes inconsistent articulation and production of speech sounds, and errors producing sounds in the correct order so that spoken words or phrases become difficult to understand.
  • Cluttering (also called "tachyphemia") - includes increased speaking rate, incorrect rhythm, intonation, and co-articulation of sounds, and other influency in speech that is sometimes similar to stuttering.
  • Dysarthria - involves weakness or complete paralysis of muscles that are necessary to produce speech, including lips, lungs, throat, tongue, and others.
  • Speech sound disorder - involves difficulty or inability to produce certain sounds or patterns of sound and sometimes results in addition, distortion, omission, or substitution of such sounds with others.
  • Stuttering - includes influency in speech, repetition of individual sounds or entire words and phrases, and misplacement or prolongation of pauses and sounds during speech that is different from cluttering.
  • Muteness (also called "mutism") - involves inability to speak due to different reasons such as anxiety, brain injuries, or inability to hear and learn speech.

Examples of barriers for people with speech disabilities

  • Web-based services, including web applications, that rely on interaction using voice only
  • Websites offering phone numbers as the only way to communicate with the organization

back to page contents

Visual

Visual disabilities range from mild or moderate vision impairments in one or both eyes ("low vision" or "partial sight"), to substantial and uncorrectable loss of vision in both eyes ("blindness"). Some people have reduced or lack of sensitivity to certain colors ("color blindness"), or increased sensitivity towards excessive brightness in colors. These variations in perception of colors and brightness can be independent of the visual acuity.

More about visual disabilities

People with visual disabilities typically rely on changing the presentation of web content into forms that are more usable for their particular needs. For example by:

  • Enlarging or reducing text size and images
  • Customizing settings for fonts, colors, and spacing
  • Listening to text-to-speech synthesis of the content
  • Listening to audio descriptions of video in multimedia
  • Reading text using refreshable braille (small dots that are raised and lowered to display characters that are read by scanning over the raised dots using the fingertips)

For these web browsing methods to work, developers need to ensure that the presentation of web content is independent of its underlying structure, and that the structure is correctly coded so that it can processed by software and presented in different ways. For instance, some people do not see the content and need lists, headings, tables, and other page structures to be properly coded so that they can be identified by software.

Some people are only seeing small portions of the content at a time or are perceiving the colors and design differently. Some people are using customized fonts, colors, and spacing to make the content more readable, or they are navigating through the content using keyboard only because they cannot see the mouse-pointer. An accessible design supports different presentations of the web content, and different ways for interaction.

Examples of visual disabilities

  • Color blindness - includes difficulty distinguishing between colors such as between red and green, or between yellow and blue, and sometimes inability to perceive any color
  • Low vision - includes poor acuity (vision that is not sharp), tunnel vision (seeing only the middle of the visual field), central field loss (seeing only the edges of the visual field), and clouded vision
  • Blindness - substantial, uncorrectable loss of vision in both eyes
  • Deaf-blindness - substantial, uncorrectable visual and hearing impairments

Examples of barriers for people with visual disabilities

  • Images, controls, and other structural elements that do not have equivalent text alternatives
  • Text, images, and page layouts that cannot be resized, or that lose information when resized
  • Missing visual and non-visual orientation cues, page structure, and other navigational aids
  • Video content that does not have text or audio alternatives, or an audio-description track
  • Inconsistent, unpredictable, and overly complex navigation mechanisms and page functions
  • Text and images with insufficient contrast between foreground and background color combinations
  • Websites, web browsers, and authoring tools that do not support use of custom color combinations
  • Websites, web browsers, and authoring tools that do not provide full keyboard support

Sections related to visual disabilities

Stories of web users:

Diversity in web use:

Accessibility principles:

back to page contents

[Previous Page - Stories of Web Users | Top of Page | Next Page - Diversity in Web Use]