This document provides an introduction to HTML (Hypertext Markup Language) and basic HTML tags. It explains that HTML documents describe web pages using tags surrounded by angle brackets. An HTML file must have a .htm or .html extension. It then discusses how the web works using a client/server model and HTTP protocol and defines a web page as a text file containing HTML markup tags that provide structure and formatting. The document gives a simple example HTML code to create a heading and shows how tags normally come in pairs. It also provides an overview of common HTML tags.