What are aria and role attributes?

Question

HTML

For an hour now I can’t understand what the aria attribute is for? For example aria-hidden="true" ? It does absolutely nothing and I don't understand how to use it.

Answer 1

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Suppose, when interacting with a rich Internet application (in ARIA terminology such applications are called active), the user does not view the page, but listens to it using a screen reader. The program reads one part of the page aloud, while the other part of the page is dynamically updated. ARIA live areas tell the user that a part of the page has been updated - the one that is currently out of focus...

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There are state attributes ariadisabled, aria-busy, aria-expanded, aria-hidden, and property attributes such as ariadescribedby, aria-haspopup and aria-labelledby that provide additional information about overridden elements. In practice, it is recommended to
rely on semantic elements as much as possible, but if you absolutely need to use a specific element (for example, a tree-like menu) “for other purposes”, resort to ARIA attributes. ...

Estelle Weil "Developing applications for mobile devices"
Chapter 6
Read it, it's quite interesting and useful!

Answer 2

ARIA is a standard designed for people with disabilities. These attributes do nothing but allow special programs (such as Narrator) to navigate the page. You can read more here