What is accessibility?

Definition of accessible

1a : capable of being reached a remote region accessible by rail also : being within reach fashions at accessible prices 2 : capable of being used or seen : available information that should be accessible to everyone 3 : capable of being understood or appreciated the author’s most accessible stories an accessible film 5 : easily used or accessed by people with disabilities : adapted for use by people with disabilities accessible bathrooms/doorways/seating/parking


Accessibility (often abbreviated to A11y—as in “a” then 11 characters then “y”) in Web development means enabling as many people as possible to use Web sites, even when those people’s abilities are limited in some way.

For many people, technology makes things easier. For people with disabilities, technology makes things possible. Accessibility means developing content to be as accessible as possible no matter an individual’s physical and cognitive abilities and no matter how they access the web.


Web accessibility is the practice of making your websites usable by as many people as possible. We traditionally think of this as being about people with disabilities, but the practice of making sites accessible also benefits other groups such as those using mobile devices, or those with slow network connections.

You might also think of accessibility as treating everyone the same, and giving them equal opportunities, no matter what their ability or circumstances. Just as it is wrong to exclude someone from a physical building because they are in a wheelchair (modern public buildings generally have wheelchair ramps or elevators), it is also not right to exclude someone from a website because they have a visual impairment. We are all different, but we are all human, and therefore have the same human rights.

Accessibility is the right thing to do. Providing accessible sites is part of the law in some countries, which can open up some significant markets that otherwise would not be able to use your services or buy your products.


Which kind of disabilities are we talking about?

We often tend to think about disabilities as some specific and rare condition, but there are as well temporary and situational disabilities:

visualBlindness, low-level vision, and color blindnessCataractLow-light or too-bright light
hearingDeafness, low-level hearingEar infectionBartender or passenger in a train
mobilityLoss of limb or paralysis or neurological disordersArm injuryParent with a baby in hands
verbalNon-verbalLaryngitisHeavy accent
cognitiveDyslexia, ADHD, intellectual disabilitiesDepressionStress, distraction

This chart shows which people with non-permanent disabilities would also benefit from accessibility. Don’t compare different conditions - sadness is not the same as depression.

A lot of disabilities are “invisible” - you would not know that people have them unless people would tell you. A lot of cognitive disabilities are not diagnosed. You or your friends and family members may have a disability and you may not know about it.

Disability can appear after disease, for example, people after stroke may get visual, mobility, verbal, and cognitive disabilities. Some disabilities appear with the age.

Why do we care about Web accessibility?

In modern society, the Web is as important as water, food, and other human essential needs. The UN Convention on the Rights of Persons with Disabilities recognizes access to information and communications technologies, including the Web, as a basic human right.

The Web is needed to make an appointment with the doctor, to do online shopping, to do online banking, to learn and for many other tasks.

The law

Accessibility is required by the law in different countries, for example:

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