GSM
![The GSM logo is used to identify compatible handsets and equipment. The dots symbolize three clients in the home network and one roaming client.[1]](/Images/godic/202501/15/GSMLogo.svg0303.png")
![The structure of a GSM network](/Images/godic/202501/15/Gsm_structures.svg0304.png")
![GSM cell site antennas in the Deutsches Museum, Munich, Germany](/Images/godic/202501/15/Deutsches_Museum_-_GSM_cell_site_antennas0304.jpg")
GSM (Global System for Mobile Communications, originally Groupe Spécial Mobile), is a standard developed by the European Telecommunications Standards Institute (ETSI) to describe the protocols for second-generation (2G) digital cellular networks used by mobile phones, first deployed in Finland in July 1991. As of 2014 it has become the default global standard for mobile communications - with over 90% market share, operating in over 219 countries and territories.