This is one of the biggest debate in Christian circles also...and there are two main groups that have formed from it. Calvinists believe that God has chosen who will become saved and who won't, and so there is no point in trying to convert anyone or even in trying to become saved, because if you are chosen then you will and if not there is nothing you can do but go to Hell. Non-Calvinsts, obviously, believe the opposite. It's also pretty obvoius that the guy who came up with Calvinistic view was named Calvin...gotta love the creativity!