At W3Schools you will find all the Web-building tutorials you need, from basic HTML and XHTML to advanced XML, SQL, Database, Multimedia and WAP.
The references cover all Web-building technologies, including W3C standards like HTML, XHTML, CSS, XML and other technologies like JavaScript, PHP, ASP, SQL and much more.
At W3schools you will find thousands of cut-and-paste examples. With the on-line HTML editor you can edit the examples and experiment with the code on-line.