★ Short form of Global System for Mobile Communications, is a wireless network system

★ A standard for digital cellular mobile communications

★ International roaming arrangements are enabled among mobile network operators, by providing the subscribers to use their personal mobile phones anywhere in the world.

★ GSM is considered as second generation mobile, as signaling and speech channels are digital

★ The carriers can be replaced without replacing mobile phones.

★ The ubiquity of GSM implementations is also enabling the switching between network operators, who can choose equipment from many GSM equipment vendors.

★ GSM pioneered low cost SMS implementation

★ The GSM standard includes a worldwide emergency telephone number feature.