A GSM cell phone is not capable of service without a little chip called a SIM. The SIM (Subscriber Identification Module) card is a 'smart' card that allows you to make and receive calls. The embedded circuitry located on the SIM card stores information about the services that are available to you as a local subscriber.
The SIM card identifies you to the network and contains a microprocessor chip, which stores unique information about your account, including your phone number. The SIM card, provided by a local GSM cell phone operator, snaps into the back of a GSM cell phone to make you a local subscriber.
Before you place the first call with any GSM cell phone you need two fundamental elements: the GSM cell phone and the SIM card.
As previously mentioned, it is the SIM card that determines your telephone number and NOT your cell phone. Therefore, every time you change your SIM card, you are getting a new telephone number and a new although not always different array of GSM services (caller ID, fax, data, call divert, voicemail).
SIM cards are available on a subscription basis, where just like with Sprint or Verizon you sign a contract and get a bill every month or they are available on a prepaid basis, in which case you buy airtime, as you need it.
About us -
Cell-phones-4u.com is dedicated to researching and developing the best information and content that makes it easier for consumers to research
and select among online providers in the cell phones industry
including wireless, long distance, cel phone accessories, ringtones etc.
Bookmark this site
|