Sensei's Library is a place where Go players can meet to find, contribute, and discuss any items related to the ancient Chinese board game of Go. (English), also called Wei Chi (Chinese), Baduk (Korean), Igo (Japanese).
The GameOfGo is extremely old, (as old as backgammon) and Sensei's library contains current cultural and background information as well as game rules and concepts designed to frame game situations for beginners, and develop better play.
Because Go is a hyperdynamic game, involving value judgements of sequence, influence, and exchange, computers fail to play it well at all. Relying on pure computational strength, and assuming Moore's law remains correct, it would require another 50 years or so for processors to demonstrate champion level results in Go, (unlike in chess) though this is only hypothetical.
Sensei's library contains among other things, links to study information for the absolute beginner to the very advanced.
Pages to get you started:
Originally based on PhpWiki, they have made so many mods (including goban diagramming) that they now call it GoWiki.
Sensei's Library is maintained by Arno Hollosi and Morten Pahle.