GSM phones or world phones are a popular travel tool

Global System for Mobile Communications (GSM Phones)- as the name suggest's are the de-facto standard of phones to be. GSM is an open, non-proprietary system that is constantly evolving. GSM phones or world phones great strength is the international roaming capability. This gives consumers seamless and same standardised same number contactability in more than 170 countries.

GSM phones are also referred to as world phones or triband phones (triband from the three frequencies GSM phones work on 900/1800/1900- the U.S. operates on 1900 and the new 800-850 mhz for some networks). Today's GSM phone technology is the basis of a powerful family of platforms for the future - providing a direct link into next generation solutions including GPRS (General Packet Radio Services) EDGE (Enhanced Data for GSM Evolution) and 3GSM( 3rd generation services such as mobile video etc on the GSM platform).

The perfect solution for international travel is GSM or triband/ world phones. Bear in mind that not all GSM phones will work in every market. As illustrated by the above mentioned, world phones are 'locked' by the carriers to have them work only on their frequencies. To make cell phone calls in Europe you'll need an unlocked dual band GSM phone and a SIM card.(You'll need a triband if you intend to use the phone in the US as well as in Europe.)

Unlocked GSM phones allow the use of any SIM card, as long as the frequency capabilities are correct. (Dual Band is 900/1800 Mhz for overseas, tri band 900/1800/1900 Mhz for overseas plus North America.)

The postage stamp sized SIM (Subscriber Identity Module) card is the brains of GSM phones. The SIM card will determine the phone's number and allow access to the services that particular SIM card supports. Prices vary with country and services. With a prepaid card, you'll probably receive unlimited incoming calls from anywhere in the world, some free calling time and reasonable long distance rates (around half a Euro or less per minute to the US). There is often a service life of the card that you can extend by purchasing airtime vouchers in the country you're visiting- usually at convenience markets and news kiosks. A postpaid SIM card requires a contract that usually bills monthly. Tip: Buy an unlocked GSM phone for this purpose.

Where do I get my Unlocked GSM Phone and SIM card? Click here to shop for Unlocked GSM Phones at 1800MOBILES.com

You're best off purchasing your GSM phone/ world/ triband phone and SIM card in the US or Europe from a dealer who specializes in selling and renting cell phones for use abroad (especially true for the SIM card itself, since most countries in Europe sell SIM cards only to residents). You can activate the SIM when you get to your destination. Add calling time to the original SIM, so you don't have to change numbers each time you run out of call credit.

You can also rent a GSM phone (from Cellhire-GSM Phone Rental). Remember, the rent on the phone along with the high usage rate often makes purchase a better deal- you will probably pay for the phone after the first trip if you make many calls.

Thus, determine your exact need for a GSM phone, including frequency of travel abroad. If you are a light traveler a GSM phone rental is a more likely choice. On the other hand a triband phone(unlocked) may be the perfect solution if you travel often- allowing you to use sim cards from different countries. This option will offer great savings over roaming rates.

Click here to read FAQs about GSM phones/ world phones and their usage in conjunction with SIM cards.