> [HTML] itself was influenced by similar efforts like SGML, but has since evolved into a lot more. Time for some pedantry: HTML is/was envisioned as SGML voca

> [HTML] itself was influenced by similar efforts like SGML, but has since evolved into a lot more. Time for some pedantry: HTML is/was envisioned as SGML vocabulary, ie. using SGML as markup meta-language to describe the elements, content models, attributes, predefined entities, and other parsing rules for HTML such as tag inferences and attribute shortforms. Or at least TBL tried to. Also, the basic rich text vocabulary of HTML for paragraphs, spans, headers, etc. is already used in ISO 8879 (SGML) as a commonly used "folklore" markup convention, with only the anchor element (<a>) and a couple others being genuinely new. And finally, "similar efforts" at the time would be HyTime (also an SGML application) not SGML itself.