Sensei’s Library is Go’s wiki database. It encompasses pretty much any Go information that you could possibly want. It has a lot of great tips and is great for players of all levels and types. Since it’s a collaborative website, the clarity of the information is not always as consistent. This is not a huge problem though, since most of the articles I’ve perused through so far have been pretty solid.
My favorite part is the fact that if there is ever a term in the article that is confusing, they generally have already anticipated such confusion and hyperlink it to its definition. And trust me, I’ve been confused plenty of times (e.g. shicho (a ladder)… ponnuki (the diamond shape made from a one stone capture)….).
Sensei’s Library will definitely be on my list for places to hit whenever I’m confused or don’t know where a term is, and it should be in your repertoire as well.