The EDGE network is the data network used by Apple and AT&T in the first-generation iPhone. It allows iPhones to send and receive data such as emails and web content, in addition to making phone calls.
The EDGE network provides average data transfer speeds of 75-135Kbps.
Apple’s choice of EDGE as the first iPhone’s data connection standard was controversial, since a faster technology, called 3G, was already widely deployed in Europe and was fairly well support in the U.S. Devices using 3G have data rates of up to 384Kbps.
Apple defended its use of EDGE by saying that devices using EDGE require far less battery power than 3G, a major concern with the first-generation iPhone.