The document describes various tags used in Hypertext Markup Language (HTML) to define text formatting, lists, tables, images, and layout of web pages. It provides examples of common tags like <p> for paragraphs, <h1> - <h6> for headings, <ul> and <ol> for unordered and ordered lists, <table>, <tr>, and <td> for tables, and <style> for defining styles. It also lists tags for images, buttons, forms, and controlling color and layout of web pages.