Accessibility is about who can use what you build

A website, web app, tool, browser, or other web technology is accessible when it is designed and built so that people with disabilities can use it. This includes all disabilities that affect access to the web, spanning auditory, cognitive, neurological, physical, speech, and visual conditions.

While accessible design also benefits people without disabilities, the primary audience should always be people with disabilities. A common pitfall for developers is assuming every user can see a screen and operate a keyboard, mouse, or touchscreen. That assumption can produce experiences that work well for some but act as anything from an annoyance to a total blocker for others.

Designing for real user needs

Accessibility concerns fall into four broad categories that should guide planning:

  • Vision
  • Motor and dexterity
  • Auditory
  • Cognitive

Addressing these means considering users who experience some type of impairment or disability in one or more of these areas. For example, a user's constraint might be temporary or situational, such as trying to read a screen in bright sunlight or using a device one-handed while holding a coffee.

Planning for these situations from the start results in an experience that is more robust and works for more users, regardless of their ability or current context.

Vision

Vision impairments span low vision to total blindness. Users with limited vision often combine screen magnification, high contrast themes, and text-to-speech. Others depend on a screen reader or braille display to navigate, perform actions, and read descriptions of content and controls.

Motor and dexterity

Motor impairments can prevent use of a mouse, touchscreen, or other pointing device. In such cases, users may rely on alternative inputs: a keyboard, head- or eye-tracking software, switch devices, sip-and-puff devices, or voice access.

Auditory

Hearing impairments can range from difficulty perceiving certain frequencies to an inability to hear sound, and may include speech processing issues. For these users, captions or transcripts are essential to provide an alternative to audio in an interface.

Cognitive

Cognitive impairment is a broad area, including conditions like ADHD, dyslexia, and autism. Accommodations vary widely, but a common thread is the need to minimize distractions, flashing content, heavy animation, or anything that shifts a user's context around the page unexpectedly. Some users will also apply custom colors and styles to improve readability or avoid headaches.