Unlocking a handset is often used to make any GSM phone work with any GSM network. Phones generally come pre-programmed by the manufacturer to work only on certain networks. These phones are called “locked” phones. GSM carriers supply phones that work by using a SIM card. If you unlock a phone, you can use the SIM card of another provider in your phone. Writer Bio

How to Unlock a Cell Phone With a Password - 80