Smartcards - © Copyright 2004
All cell phone services have two main components, the cell phone
itself (the handset), and a small chip inside the cell phone called the SIM
card. SIM stands for Subscriber Identification Module.
To better understand what each does, here's a simple analogy.
Think of the handset, the cell
phone itself, as the phone you have at home. You probably went
to an electronics or general merchandise store (Best Buy,
Wal-Mart... etc.) and bought it from there. You may have
decided to buy the most inexpensive phone there, the one with the
most features or something in between.
No matter which phone you chose,
you must have a phone number activated and connected from the local
phone company for any of the phones to work. The phone number
account you get from the local phone company and have connected to
your home phone plugs is equivalent to the SIM card in cell phones.
If you unplug your home phone and
take it over to the neighbor's house and plug it in the phone outlet
there, the phone will only ring if someone dials your neighbor's
phone number. It will not ring if people are dialing your home
number. If you place a call from your phone from the
neighbor's house, the charges for the call will show on your
neighbor's phone bill and not yours.
This is exactly the same in the
case of cell phones and SIM cards. If you remove your SIM card
and put your brother's SIM card in your phone instead, the phone
will act in the same way described above. YOUR phone
will ring when callers dial your brother's cell phone number. Placing
calls will take from his balance that is on the SIM card (if he is
on a prepaid plan) or charge his account if he is a postpaid
subscriber. In effect, YOUR phone is now HIS
There are many cell phone
systems available. This relates not to the brand or the model of
the phone but the inside technology that operates it. The analogy
would be the voltage in your electric socket, 110 in the USA vs. 220
in Europe and the Middle East. CDMA and GSM are the most used.
CDMA is the cell phone
system that is most common in the USA even though the GSM is growing
GSM is the
wireless phone used throughout Europe, the middle East, Asia, Africa, and
is recently becoming more popular in the US and Canada. GSM stands for Global Systems for Mobile Communication.
All cell phones available at InTouch Smartcards are
phones. All phones offered on this
website are unlocked and can be used by simply inserting a SIM card.
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