Pokertracker

I was contemplating trying out pokertracker, the free trial version, because I have heard people say it helps. What can you learn by using pokertracker, how does it help you, is it worth the 50 bucks, and how do you start using it? i cant figure out how to put the information in to it. sorry i was just brainstorming all of my questions there. any answers would be helpful. thanks in advance