by
Zaid Rabab'a , Software Development Team Leader , Al-Safa Co. Ltd.
www.w3schools.com/ best place for beginners
then you must chose what you want to be expert on it
like php, asp.net , or maybe ruby
im php specialist you can try YII framework
www.yiiframework.com/tutorials/
by
Hazem Salama , Senior Member of Technical Staff , Verizon Communications
I would not recommend w3schools site since it contains a lot of misinformation, see here http://w3fools.com/
I'd suggest more reputable site such as:
http://www.codecademy.com/
http://www.codeschool.com/
http://teamtreehouse.com/
Some of those site charge money for some of their premium content (much like http://net.tutsplus.com) but a lot of it is free.
Cheers!
For absolute beginners,
HTML, CSS, PHP: [http://www.w3schools.com/] is good and interactive
Javascript, Ruby on rails: [http://www.codeacademy.com/] is a great website, full of interactive and useful problems...
PHP frameworks (if you already know PHP): Yii framework has one of the best and easiest tutorials and reference guides available online [http://www.yiiframework.com/tutorials/]
For Pros: I really recommend reading the references and standards along the execution of any real project, invent one!
W3schools is very useful but their information is very basic and sometimes they tend to omit critical details.
For advanced HTML and CSS: http://www.htmldog.com/
For advanced PHP and MySQL: http://www.tizag.com/