The document provides a reference guide for HTML5 tags including the tag name, which HTML versions the tag is valid for, and common attributes for each tag. It lists over 100 tags across 4 pages, providing brief descriptions and allowed attributes for each tag. Key tags covered include common text tags like <p>, <strong>, headings, lists, forms, media, semantic sections, and tables. The quick reference guide serves as a concise overview of HTML5 tags and their attributes.