Gsm (GSM) or System Global Mobile Communications is one of the most commonly used standard mobile phones in the world. The main dealer, it's now GSM estimates that 80% of the market of global mobile phone of this standard. Three billion people in 212 countries from the standard interest will fall.The extensiveness of the standard international roaming between mobile phone operators common). This possibility to subscribers, enabling their cell phones in most parts of the world.

GSM, in principle, short words, the French Groupe Spécial Mobile (Group Special Mobile). The GSM technology earlier in the signaling channel, digital voice and that is why it as second generation mobile systems (2G) will be remembered. Also GSM for the first time, a cheap alternative (for network carrier) for the phone calls, offer. short message service(SMS), which is nowadays in other standards of the mobile phone is also supported. A another advantage of it is that the standard includes an emergency number ... 112,.

the newer version with the standard of the original GSM phones are compatible. For example, in version 97 standard functionality of the package data with the use of GPRS has been added. Version 99 with the use of technology EDGE send high-speed data offer.