HTML – ;Hypertext Markup Language HTML is the language for publishing hypertext on the World Wide Web. This scripting language can be created and processed by a wide range of tools, from simple plain text editors - to sophisticated WYSIWYG (What You See Is What You Get) authoring tools. HTML uses tags to structure text into headings, paragraphs, lists, hypertext links etc. A convenient way to automatically fix markup errors is to use the HTML Tidy utility. This makes the document easier to read and edit. Tidy is very effective at cleaning up markup created by authoring tools with sloppy habits. Tidy is able to fix up a wide range of problems and to bring to your attention things that you need to work on yourself. Each item found is listed with the line number and column so that you can see where the problem lies in your markup. Tidy won't generate a cleaned up version when there are problems that it can't be sure of how to handle. These are logged as "errors" rather than "warnings". HTML has three variants. You specify which of these variants you are using by inserting a line at the beginning of the document. Each variant has its own DTD - Document Type Definition - which sets out the rules and regulations for using HTML. When you want to use a tool to validate the HTML document, the tool will know which variant you are using. Transitional – ;Used when writing Web pages for the general public, when pages are accessible for viewing in older browsers. An advantage here is the support of style sheet, which include different features used in BODY such as bgcolor, text and link attributes. *!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html401/loose.dtd"* Strict - Used when we want