Atheism is not a belief, its a disbelief in Religion.Atheists believe in nothing, For Nothing is where the universe came from ! From nothing came everything ! I think it is far more logical to believe in a God than to believe in a scientific proven impossibility that is called "Nothing "
Think of anything you can that is Religious. Now disbelieve it, and you have Atheism.
Most Atheists disbelief religion for different reasons. Some reasons are:
1. No evidence of god.
2. Strong evidence that religious people lie about god
3. Religious books full of psychotic drivel and no bearing on reality
4. Violence and hate created by religion