The document provides an introduction to HTML (Hyper Text Markup Language), which was first proposed by Tim Berners-Lee in 1991 as a standard for displaying hypertext documents on the World Wide Web. It explains that HTML is a markup language comprised of tags that describe how text and other content is structured in a web page. Some key HTML tags are described, such as tags for headings, paragraphs, links, lists, and basic text formatting. It also provides an example of a simple HTML document and discusses how web browsers interpret and display HTML pages.