w3schools
w3schools
W3Schools is a web developer information website, with tutorials and references relating to web development topics such as HTML, CSS, JavaScript, PHP, and SQL.

The site derives its name from the abbreviation for the World Wide Web; W3 is a numeronym of WWW. W3Schools is not affiliated with the W3C.

It is created and owned by Refsnes Data, a Norwegian family-owned software development and consulting company.
Reference
Wikipedia
Web References
W3C
w3schools
Wikipedia