HTML 3.2 was the latest non-dynamic HTML specification. It was supporting Netscape Frames and tables before the arrival of HTML 4 which brought dynamic HTML and CSS (Cascaded Style Sheets).
This flavour of HTML was fully supported by the Acorn Network Computer.

HTML 3.2 was the first HTML standard dedicated to encoding whatever hacks Netscape had implemented into their browser. Earlier versions, most notably HTML 3.0, also devoted effort to this task, but they additionally included many extensions to HTML that Netscape did not support. (Some other browsers do support them.) Netscape still isn't fully standards compliant and it will never be, but the differences have been much reduced.