In this mod, you can basically lead your "second life". There are many possibilities and probably many more will be added in the future. You can become a police officer and live by the law or you can become a criminal and rob everything and everyone - although once you get caught, you well get into prison. You will need a driver's license in order to buy your own car which you can lock, so that no one else can get into it. You can buy the right to carry a weapon and to use it for self-defense, in case you get attacked. The amount of money you get depends on the server, but it will definitely increase if you find a job.
It's hard, however, to find a good server. Most of them are not controlled by their administrators, and both police and civilians do whatever their hearts desire.