XML

Note that many of these developments were originally done with extensions to HTML. Most developers are now moving to XML (Extensible Markup Language), which is better suited to coding information like text to speech, information in tables.

HTML has been great for presentation, but the Web is becoming more than just a presentation medium. It is becoming an electronic commerce medium, and the pages the people exchange must become more than just large blocks of unknown information. XML can explicitly describe a piece of information such as an address or an invoice total so other programs can extract that information automatically.