What do people do with stolen iphones?

My iphone was recently stolen, i tried to track it on icloud but it said that my iphone was offline, i also tried calling my phone and it went straight to voice mail, which can only mean two things: my phones is dead, or was turned off, So my question is if someone were to steal my phone what would they be doing with it if its turned off or dead?

Chances are it isn't turned off or dead.
Once they stole your phone, whether password protected or not, all they have to do is remove your SIM card, aka the card that your phone provider uses to track the number of minutes you spend and such, and put their own SIM card in, and boom, they can use it.

Btw if you go to your phone company you can get another SIM card

Well they are easy to restore, remove the sim card and basically you have a new phone that they can sell or use themselves.

1. Get it back from the thief/thieves
2. If they didn't do anything with it, back it up to iTunes on your PC/Mac
3. Keep doing this at regular intervals so that you can start from where you left off should you get a new phone.

Call the service to track it.