W3 Schools
My Opinion, I see w3 schools as a referencing site more than a tutorial site. It is the best referencing site ever. Even for now, I still under-use it's magnitude, this is because I only use the HTML/CSS aspect of it. But I know, I will definitely touch it all... very soon.
It is a popular web site for learning web technologies online. It's content includes tutorials and references relating to HTML, CSS, JavaScript, PHP, SQL, Bootstrap, and jQuery. It receives more than 10 million unique visitors monthly and you can be one of them.
Visit w3 schools for tutorials and referencing... you'll be a better programmer.
