InTouch SmartCards
Wireless experts serving travelers since 1987!

SmartForward: ONE USA Number 
anywhere you go!  More info >

  $20 off our Select Free Travpak
Use e-code
  Smart Deal:  
Unlocked Triband GSM Phone under $100!

iSIP International Phone Service For iPhone and Blackberry
  Try before you buy:
Apple iPad Rental with International Calling!
  $15 off SmartFree Quattro
Use e-code QUATTRO
Reviewed  by:

Information Center: Overview - Unlocked GSM Phones - SIM Cards - Thuraya Satellite - Globalstar Satellite - Iridium Satellite

Most Popular SIM Cards:  SmartFree Quattro 44 Global SIM - Travel International SIM - SmartRoam Global SIM Card - USA Gold - All Prepaid International SIM Cards
Online Reloads: Travel International SIM - Smart Roam Global SIM  - USA 380 - USA Gold  - SmartStart Gold - Iridium - Thuraya
Search Product List

Product Search


World Phone Bundles

SIM Cards

Value GSM Phones

Flip GSM Phones

GSM Camera Phones

Quad-Band World Phones

3G Global Phones

GSM Smart Phones

Entertainment GSM Phones

GSM Phone Brands
   Apple iPhones
   Blackberry Phones

   Sony Ericsson

Satellite Phones

Reload Center


Return Call Back Service

Buy Calling Account

Login Calling Account

SmartForward US Number

International Origination
Calling Card

Information Center


Job Openings

Prepaid Calling Cards

International Phone Cards

Information Center: Cell Phones: The 2 main components

InTouch 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 phone.

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 rapidly.

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 Unlocked GSM phones.  All phones offered on this website are unlocked and can be used by simply inserting a SIM card.

Click here for the next article that gives you an idea what an Unlocked GSM phone or skip to the article that talks about SIM cards.

Back to Information Center

bottom_side.gif (1941 bytes)

|  Home  |  Contact Us  |  Shipping  |  Privacy  |  Returns  |
|  Travel Center  |  Rentals  |  Affiliate  |

bottom_side.gif (1941 bytes)

Site Design by: A Design Elf Site