GSM is the abbreviated form of global system for mobile communications. This term denotes a standard for second-generation radio based mobile communications established to promote compatibility between mobile telecom services and mobile communications devices. It is sometimes referred to as 2G. The first network built on the GSM standard was launched in 1992.
The GSM standard was built around mobile telephony and SMS messaging. It is also possible to transfer data and connect to the Internet through GSM networks using GPRS or EDGE technology, but data transfer speeds are relatively low. GSM networks are less efficient than networks built on the newer 3G/UMTS, 4G/LTE and 5G standards.
In order to connect to a GSM network, you must use a mobile phone or other mobile device which supports GSM technology. Currently, all mobile phones produced are GSM-compatible.
Swiss telecom service providers Swisscom, Sunrise and Salt all maintain GSM networks. Swisscom and Salt have both stated that their GSM networks will be phased out in the year 2020. It is possible that Sunrise too will phase out its GSM network in the future.
A handful of countries are not covered by any GSM networks. In Japan and South Korea, for example, a different standard for second-generation mobile communications was implemented.
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