2G

2G, or second-generation wireless network technology, refers to the set of mobile telecommunications standards introduced in the 1990s that digitalized voice services and added data capabilities. It succeeded 1G analog networks and enabled features such as text messaging (SMS) and basic mobile Internet.

Technologies and standards: The best-known 2G family is GSM (Global System for Mobile Communications), which uses SIM cards and digital signaling. Other 2G technologies include the IS-95/CDMA family, which underpins CDMA-based networks in North America and elsewhere, with later evolution into CDMA2000 1xRTT providing higher data rates. Data enhancements in 2G include GPRS (General Packet Radio Service), often called 2.5G, and EDGE (Enhanced Data rates for GSM Evolution), also called 2.75G, which introduced packet-switched data and higher speeds.

Data rates and performance: GPRS typically offers tens of kilobits per second, while EDGE can approach a few hundred kilobits per second under favorable conditions. Actual user experience varies with network load, spectrum, and device capability.

History and deployment: GSM, the dominant 2G technology, was first deployed in the early 1990s (with early commercial launches around 1991–1992), and rapidly expanded worldwide. CDMA-based 2G networks began in the late 1990s in North America and elsewhere. 2G laid the groundwork for mobile Internet, messaging, and roaming.

Legacy and status: In many regions, 2G is being phased out in favor of 3G/4G/5G, but it remains in use in some markets mainly for SMS and voice, often with long-range coverage and low power consumption for simple devices and IoT applications.