Best Reference Site For Each Programming Language?

Howling writes "I've been a PHP programmer for a few years and after taking a trip through many sites Ive learned that www.php.net is probably the most complete source when looking for information/documentation. I have been trying to find similar sites for every other language (Java, perl or ASP, for instance) without equal success, though. I ask: what is the best documentation/reference site for your preferred programming language?"