Unlocked Cell Phone?? What?

Unlocked phone means you can use it with any carrier that supports that technology. GSM phones are the ones that use sim cards. Bell does NOT use sim cards in their phones but AT&T does. If you have your phone unlocked (a gsm phone for instance) you can use it with any gsm carrier in the world- any carrier that accepts sim cards. For example, if you no longer wish to be with AT&T you can use your phone with another service like Cingular for example.