You search using google and wikipedia, aren't you? Many useful documents are allowable, don't you think so? In addition, it's free! Aren't you only receiving them? You should also post some information that you know, don't you think so? You should post the information aggressively even if you are not confident; you don't need to care about it since most people knows that the internet is full of fakes. The people who have knowledge should post it so that everyone can receive the knowledge as much correct as possible. Any information is welcome; posting some knowledges and make the certainty of internet high leads to the public benefit.