HTML is used to create web pages. It uses tags to define text formatting, images, links, and other page elements. Some key tags include <b> for bold text, <i> for italics, <img> to insert images, and <a> for links. Forms can be created using tags like <input> for text boxes and buttons, and <textarea> for comment boxes. Well formatted HTML pages include a <head> with <title>, and a <body> where content is placed.