abbr. 全球移动通信系统（Global System for Mobile Communications，第二代数字蜂窝移动通信标准）；克每平方米（grams per square metre，纸张克重单位）；销售总经理（General Sales Manager）；政府标准手册（Government Standards Manual）
abstract:GSM (Global System for Mobile Communications, originally ), is a standard set developed by the European Telecommunications Standards Institute (ETSI) to describe protocols for second generation (2G) digital cellular networks used by mobile phones. It became the de facto global standard for mobile communications with over 80% market share.