GSM (Global System for Mobile Communications) is today rated as the most used and preferred standard for mobile phones worldwide. The reason for the increase in demand of GSM network is that it provides a higher digital voice quality. On top of it, GSM network introduced certain cost effective alternative tools for calls like short message service, cheaper call rates to similar GSM networks and the like.

The Most Common Digital Mobile Phone Service in the US is CDMA
CDMA (Code access division multiple access) is a version of multiplexing that allows manifold access without breaking them up into channels as in TDMA or FDMA. It encrypts the data with special coding connecting to each individual channel. CDDMA uses thee constructive interference feature of these specific codes to function the multiplexing. Therefore, in the US it is used at large but not globally. The reason to this difference is because CDMA compared to GSM falls expensive.
The World uses GSM
As mentioned before GSM is the most used standard of mobile phones globally. There are various advantages offered by GSM due to which it has managed its way to success. Through GSM network international roaming has been made very common among phone operators. This allows the subscriber to use his/her phone in any part of the world. This is one of the major factors due to which GSM technology is considered better.
Usage Statistics
GSM is used in more than 210 countries and regions. According to the latest reports, GSM mobile phones are being used by more than 2 billion worldwide.