A plague on both houses. I'm exaggerating, but a good and reliable <i>example-based</i> reference documentation organised by <i>use-case</i> is what I need in 90% of cases (a comprehensive index of methods/params/etc makes up the other 10%). Neither W3Schools or MDN (nor most other docs) get this right.<p>Which is why Stack Overflow is increasingly taking the load of being my reference docs. That's scary, since I also have to filter out the untruth as I read, but the immediacy of its usefulness is hard to deny. It is effectively a massive discoverable library of <i>examples</i> organised by <i>use-case</i>.