A free book available online
And yet, despite this ubiquity, the topic hypermedia itself is a strangely under-explored concept today, left mainly to specialists. Yes, you can find a lot of tutorials on how to author HTML, create links and forms, etc. But it is rare to see a discussion of HTML as a hypermedia and, more broadly, on how an entire hypermedia system fits together.
This is in contrast with the early web development era when concepts like Representational State Transfer (REST) and Hypermedia As The Engine of Application State (HATEOAS) were discussed frequently, refined and debated among web developers.