Moderation is a great way to safeguard your content library from populating with incorrect or untrustworthy content. This link from RFPIO University will tell you a little more about it, as well as walk you through how to enable it.
An analogy I like to use is to envision your Content Library as your castle and Moderation as the moat that surrounds it. Before anything is granted entry to the castle it has to cross the moat, and the person(s) who are assigned to the Moderation queue are the ones who decide whether or not you let the drawbridge down :)
