W3Schools is a web developer site, with tutorials and references on web development languages such as HTML, CSS, JavaScript, PHP, SQL, Python, jQuery, Java, C++, C#, React, Node.js, XML, W3.CSS, and Bootstrap, covering most aspects of web programming.
The site derives its name from the World Wide Web (W3) but is not affiliated with the W3C.
W3Schools was originally created in 1998 by Refsnes Data, a Norwegian software development and consulting company.