Mobile communications:

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 December 1991. As of 2014[update] it has become the de facto global standard for mobile communications – with over 90% market share, operating in over 219 countries and territories.