GSM

Global System for Mobile Communications, or GSM, is a digital wireless technology standardized to create a compatible wireless network across Europe. GSM is most commonly used in Europe, but it is also deployed in other areas of the world, including the United States. GSM operates in 3 frequency ranges - GSM 900, GSM 1800, and GSM 1900 (also called PCS 1900). The fourth generation of GSM (4G) is a bit nebulous, but the industry has agreed that Long-Term Evolution (LTE) will be the next logical step in GSM's progress.