The lock/unlocked refers to the phone being coded for a specific carrier/geography. If its a locked phone for verizon, you can't cancel the service and take the phone to AT&T and get service from them using the same phone. But like any good technology, that can usually be hacked and deactivated so the phone would be unlocked. Then, as long as the phone uses the same cell technology as the carrier you want to use, you can use the phone.