When W3Fools was launched in 2011, the state of documentation for developers was poor. This site documented many content errors and issues with the W3Schools website. The Mozilla Developer Network was around but it did not have much support at the time.

Today, W3Schools has largely resolved these issues and addressed the majority of the undersigned developers' concerns. For many beginners, W3Schools has structured tutorials and playgrounds that offer a decent learning experience. Do keep in mind: a more complete education will certainly include MDN and other reputable resources.