A big focus of mine is accessibility in tech. This stems from working with people at the Apple store and experiencing how frustrating it is when an update happens automatically and it erases all customized settings a person who is blind has spent time perfecting. Or when a screenreader isn't able to deliver semantic tag or role readings because a website doesn't include them.
ARIA is a set of html attributes designed to offer semantic info for screen readers. So there are two sites and a video below that have been helpful to me. I'm still studying but needed a place to dump the good resources I've come across.