| GSM (Global System for Mobile Communication) is | | | | used with the GSM SIM cards from different |
| the most widely used wireless mobile | | | | service providers. Thus, if you are planning to shift |
| communication technology in the world. GSM cell | | | | to a new mobile service provider (such as |
| phones are highly popular in Asia, Europe and | | | | AT&T, T-Mobile and Cellular One), you are |
| Australia due to its excellent coverage and | | | | not required to dump your phone. Every time a |
| flexibility, as against to CDMA (Code Division | | | | new SIM card is inserted into the GSM phone |
| Multiple Access). | | | | device, it starts receiving network connection |
| What is a GSM Cell Phone SIM Card? | | | | from the new carrier. |
| Unlike CDMA technology, the GSM cell phones | | | | When visiting a foreign nation with GSM network |
| utilize SIM (Subscriber Information Module) cards. | | | | available, it is possible to buy a local SIM and save |
| Simply put, a SIM card is a just like any other | | | | on the international roaming charges. However, |
| smart card, such as a credit card. It contains | | | | you have to provide some documentation to |
| information about user's service subscription and | | | | procure a new SIM in a foreign nation. Also, you |
| account settings. It allows the cell phone to access | | | | will be able to buy only prepaid GSM SIMs which |
| the service network through wireless technology. | | | | require you to pay in advance for services. |
| A SIM card also stores essential data such as | | | | It is essential to know that GSM phone devices |
| user's subscription numbers, phone number, | | | | work on a specific frequency bands for wireless |
| security codes and personal contacts. The most | | | | communication. Dual band works in the frequency |
| important benefit of using a SIM card-based cell | | | | 900mhz (megahertz) to 1800mhz. Most of the |
| phone service provider is that the card can be | | | | countries follow dual band for GSM services. |
| used in different cell phone devices. Thus, you can | | | | However, North America is an exception as the |
| retain the same number while sporting new cell | | | | region operates on 1900mhz. To ensure that your |
| phone devices. | | | | cell phone continues to operate across the world, |
| What are Unlocked GSM Cell Phones? | | | | buy a Quand band GSM device. |
| Unlocked GSM cell phones are devices that can be | | | | |