Can you tell me the best describes the basic functionality of HTML in Web communications?

Answer 1

Pretty much everything is explained here I guess
https://www.sololearn.com/learn/HTML/1021/

Answer 2

HTML provides structure to documents using codes for headings, titles, lists, paragraphs, and other semantic elements so that they can be displayed by ordinary web browsers.

Answer 3

You can think HTML as skeleton of a web page, JAVASCRIPT as muscles of webpage, CSS as outer appearance or skin of webpage