the way it works (pretty much). Is that the Judge will let you out of jail if you deposit a bond (lets say $20,000) that you will get back when you go back to court.
If you do not have the money you can pay a bail bonds man (usually 10% $2,000), and they will deposit the bond.
when you appear in court the bail is returned.
if you do not return to court the bail bondsman is out of the full bail. And they will pay Bounty hounters to track you down and put you back in jail so that they can get their money back.