1. There is an official definition of 3G, but "4G" is just a marketing term so far. A 3G network must consistently deliver speeds of over 144 kbps, while moving. Still, even though 4G has no real meaning, it's a useful term to describe newer, incompatible networks which follow 3G.
2. 3g internet providers commonly advertise hi-speed Internet connection, but it is a trick. You won`t get this advertised speed, because it is the maximum speed that provider can give you. Of course, 3G internet speed depends on the numbers of users and their activity. OGO may serve here as an example. At first the speed and ping was pretty good, then a company gave Internet access for too many users and and it was almost impossible just to surf the Net during evenings. My friend likes on-line games, so he had to wait until 3am in order to play without errors and glitches.
3. There is one thing that I liked much - continuous signal. This means that if a person goes in train, for example, and uses 3g Internet, the connection will be uninterrupted, if the coverage is good. If you getting farther from one station and the signal gets weaker, another station will "catch" you without any break of connection.
1. The CDMA technology provide the least delay, comparing to the other ways of mobile connections
