SIM (Subscriber Identity Module) is a "smart card" used in digital phones by a subscriber to GSM (Global System for Mobile communications).
It carries the user's identity for accessing the network and receiving calls and also stores personal information, such as phone directory and received SMS messages. The SIM card can also be plugged into another GSM phone. This allows the user to use another GSM phone as if it was his/her own phone.
In order to obtain the services available, a customer will need to acquire a FSMTC SIM card. This SIM card will give the customer a mobile telephone number that will become the customer’s account. FSMTC SIM card are sold without airtime on the account. In order to gain airtime, a customer will need to purchase a FSM TelCard then transfer the value of the FSM TelCard into his or her cellular mobile number. The following are the rates currently applicable to the cellular mobile services rendered on the FSMTC’s network.