This is the most exhaustive reference for all things web development! It should be considering these are the guys who decide what the whole browser language should be and act like. If it were not for this great resource I would be left in the lurch for many a problem I have face in writing good code.
I hope they continue to progress with their schools program to educate more people in what is the language of more and more business these days. So if you are in the market for learning about all things web, then this is almost a one stop reference!