Global System for Mobile Communications (GSM)

Originally Groupe Spécial Mobile. A standard set developed by the European Telecommunications Standards Institute to describe protocols for second generation digital cellular networks used by mobile phones. Developed in the 1980s, GSM was first deployed in seven European countries in 1992. Operating in the 900 MHz and 1.8 GHz bands in Europe and the 1.9 GHz PCS band in the United States, GSM defines the entire cellular system, not just the air interface.