Hyper Text Markup Language
Read about HTML
Description
Hyper Text Markup Language (HTML) is used to structure a website's content. The code consists of tags that describe different elements on a web page (for example <h1></h1> for a heading or <p></p> for a paragraph). So-called identifiers or classes can be added to a tag. This makes it possible to attach a certain presentational style to an element through the use of CSS.
The HTML 4 specification can be found here: http://www.w3.org/TR/html4/
Resources
Reference: http://reference.sitepoint.com/html
Current developments
The big news in 2009 was that the W3C abandoned work on the new version of XHTML in favour of HTML. I haven't mentioned XHTML so far. It is not really that different from HTML. It is a reformulation of HTML using XML. This means that there are stricter rules. For example, all elements have to be closed, and have to be correctly nested.
The next version of HTML will be HTML 5 which will have a lot of new elements. It is not expected to be finalised any time soon, but some browsers already support part of it. A good way to keep up to date is following Jeremy Keith's blog where he regularly posts about new developments: http://adactio.com/journal/tag/html5