From ArticleWorld

HTML (HyperText Markup Language) is a markup language with hypertext support design to create pages viewable in web browsers. It is, along with its variation, XHTML, a current standard in web designed. The original definition was given by Tim Berners-Lee, but HTML is an international standard (ISO/IEC 15445:2000). Unlike XML, HTML does not define the kind of information itself, but rather a way of interpreting and rendering it in a visual form by a client program. HTML lacks many qualities of other hypertext-oriented languages or systems, but it has become widely accepted because of its simplicity and usability.

An HTML document contains various markup elements, which define each final element of a web page.

Element types

  • Structural markup describes the function of a text. The appearance can be defined using additional CSS styles, but standard appearance is defined for each of these. For example, text placed in an

    element will be rendered with a large, bold-faced font.

  • Presentation markup describes the appearance of a text, independently of its function. A number of standard presentation elements exist, to allow text to be bold, italic, underlined, emphasized etc.
  • Hypertext markup links parts (or elements) of a document with other parts or documents. This is a fundamental feature of HTML.

Relation with HTTP

HTML is the common standard for the World Wide Web. HTML pages are usually transmitted to the web browser using the HyperText Transfer Protocol (HTTP). HTML pages have a special MIME type assigned, so that the client will know what to do with them, as HTTP can be used to transfer any kind of file format. Documents are prefaced by a special DTP (Document Type Declaration) which states what standards they are using (HTML, XHTML, XML etc.), but if the web browser does not recognize the MIME type of a document as HTML, it will not render it.

HTML e-mail and abuse

Some e-mail clients allow HTML e-mails to be sent, in order to allow for a wider range of formatting options. This has been widely criticized, because it is often overused, and assumes that the recipient also has an HTML-capable mail client. HTML e-mails also pose a number of security threats.