HTML stands for HyperText Markup Language
HTML is a markup language used to format text and multimedia documents and to define hypertext links between online documents.
HTML is used widely on the world wide web. It is the default standard for building websites. There are many HTML books available and many online sites which can guide you through learning the basics of HTML.
A solid knowledge of the basic HTML tags is essential for any would be webmaster. There is no need to be scared by HTML, it is much simple and fairly intuitive. There are less than 50 tags that you must master to build a basic website, and it can be done with much less.