The new 1xRTT network (commonly know as 1x) provides the foundation for an entirely new generation of mobile applications offering you the ability to personalize your phone with services such as ring-tones and screen savers or download a game if you are so inclined. 1x is an enhanced CDMA network but with a faster more efficient way of transmitting data and checking emails. The key benefit of 1x is its capabilities of transmitting data at speeds of up to 153 kilobits per second but on average you will experience transfer speeds of 50 – 100 kilobits per second*. This is considerably faster than CDPD service with a peak data transmission speed of 19.2 kb ps. Mobile Browser service and Digital Data to GO are circuit-switched services that transmit at only 14 kb ps. Once a data session is initiated on 1x it uses an “Always On” connection, which means you are only billed for the data transferred, rather than time used.
*Transfer speeds quoted are as per CDG (CDMA Development Group) http://www.cdg.org/

Global System for Mobile communications (GSM): This is the operating system standard in Europe, Asia, Australia & Africa, It is also used in a similar fashion in areas of North America but again this has a twist! The European GSM signal differs from that used in North America so be careful when purchasing a phone that you think will operate all over the world - it won't. In Canada GSM is available but only in very limited areas such as major centres & corridors, so if you never go off the beaten path....... ???

Note: By changing the SIM card of your GSM phone you could use the phone in Europe and in limited North American cities but it is quite an expensive solution if you are making the changes only for a short business trip or vacation. Solution, rent a phone in the country you are travelling to.