GSM is an open, digital cellular technology used for transmitting mobile voice and data services and is the world’s most widely used cell phone technology.
GSM is the legacy network of the evolution to the fourth generation (4G) technologies Long Term Evolution (LTE) and LTE-Advanced. The following diagram represents the evolution of what is commonly referred to as the GSM or 3GPP family of technologies from second generation (2G) GSM and General Packet Radio System (GPRS) to Enhanced Data for GSM Evolution (EDGE), to (3G) Universal Mobile Telecommunication System (UMTS), also known as Wideband Code Division Multiple Access (WCDMA), and High Speed Packet Access (HSPA)UMTS and HSPA, and then to the 4G LTE and LTE-Advanced technology.
In 1982, a consortium of European countries created the Group Spéciale Mobile (GSM) to develop a cellular technology that would provide seamless international roaming and support for advanced services not available on analog networks. The European Telecommunications Standards Institute (ETSI) took over the project in 1989 and finalized the first set of technical specifications.
The first GSM network was launched in 1991, followed by several more the following year. As countries outside Europe adopted the technology, it became clear that GSM would be a global rather than European technology, so the GSM acronym was changed to stand for Global System for Mobile communications.
GSM was the foundation for the more than 6.5 billion connections using 3GPP technology.