In 1991, the 2nd generation of telecom networks were been marketed in Finland, based on GSM (Global System for Mobile communications) standards, allowing 9.6Kbps as a data rate.
Three essential advantages of 2G arranges over their predecessors were :
2.5G : GPRS
To offer higher data rates introduced for mobile, GSM started developing GPRS (General Packet Radio Service) which achieved 160Kbps.
2.75G : EDGE
EDGE (Enhanced Data Rates for GSM Evolution) introduced 8PSK modulation to reach 500Kbps using the same infrastructure og GPRS