I don't read them most of the time, all I know is that it only discusses your agreement with the service provider on not misusing their service and how they take action accordingly. Most of the time, I only read it when I need it, specially when I encounter challenges along the way with the service provider. On the other hand, who takes advice from non-readers? Joking aside, I've tried reading most part and most of them just contain how they can legally take action depending on the circumstance you get yourself into. As long as you are not a violator by nature, you are safe (hopefully).