GSM, 3G, 4G

Everyone keeps asking if my phone is 3G or 4G.

G.G.G.... It's a HTC Legend on Virgin Mobile Canada;
GSM, WCDMA, HSDPA OR in G's; it's a 3.5G

Problem is like computer technology, we have 3G and 4G phones
everywhere but the networks aren't so readily available.  Like multi-core
computing, you may have 4, 8 or 16 cores; but where do you find multi-core software.  Technology is getting better and farther apart at the same time.
As far as cell phones networks, here's a brief simple history (BTW the "G" stands for "generation"):

GSM: 2G European standard and the first digital mobile system. It offers only circuit-switched traffic (i.e voice calls, SMS...etc) and data transfer at very low bitrates 9.6kbps.

GPRS: also reffered to as phase 2+. It offered packet-switched traffic with new network components integrated over the existant GSM core network. This allowed data bitrates to increase to 171kbps. It is also considered as the first step towards 3G networks.


EDGE: It was made to cover the delay of delivery of 3G/UMTS network. It supported data rates upto 384kbps.


UMTS: the first 3G European standard network. It is the optimal solution for GSM operators to support 3G services. The Air interface technique used for this network is WCDMA. This technique allowed data rates to reach 2Mbps.


HSDPA: It is actually a software upgrade to the UMTS network using the same air interface technique used in UMTS (WCDMA) and supporting data rates upto 10Mbps.