Accessibility seems mysterious to many, but the basic concept behind it is the same as usability—someone who visits a web page should be able to read its content easily, and those who open a web app should be able to use it. An accessible web site is one that is also usable to everyone who may try to access it. In fact, many accessibility features are used optionally by able-bodied people—keyboard navigation can be quicker than a mouse for filling in forms, and subtitles in video can be useful even if you’re not hard of hearing.
Accessibility covers a large range of topics, and like much of ...