I used to use W3 schools a lot but lately have found your explanations overly complicated. For example, the php upload script is almost unintelligible. After a few hours I finally managed to break it down to two lines from about 100.
Same for dozens of other explanations. Recently I wanted to look up how to create a refresh script so I could redirect the reader to another site. I couldn't find anything.
So I googled Refresh Tag and found an explanation instantly in W3.org.