Accessibility (a11y)
In one sentence
Whether people with visual, hearing, motor or cognitive impairments can use the site.
Analogy Mental model
The ramp beside the steps. The people who need it need it completely, and everyone else barely notices it exists.
In practice What you actually do
Semantic HTML first, because a button element is accessible and a div with a click handler is not. Alt text that describes, keyboard navigation that reaches everything, contrast at 4.5 to 1, and labels attached to inputs.
Where people get burned Pitfalls
Accessibility is a legal requirement in a growing number of jurisdictions, not only an ethical one. It also produces markup crawlers read more easily, which is a side effect rather than the reason.
This entry was written in English from the Chinese original, not machine-translated. Read the Chinese version →