LABEL THE REST OF THE THINGS!Native accessible name properties that we discussed in part 1 are all great, but there are situations where these don’t suffice – where either no method for providing an accessible name exists in HTML5 or a situation arises where standard HTML5 methods aren’t enough. Enter aria-label and aria-labelledby. Aria-label and aria-labelledby are global WAI-ARIA attributes which means they can be used on all HTML5 elements although they have widest support by screen readers when used on focusable elements. Let’s look at some use cases.
Source: Accessible Names – Label All the Things! (Part 2) | Mediacurrent