Differences between 1G, 2G, 3G and 4G Technologies

1G	2G	3G	4G
Voice	Voice + Data	Voice + Data + Video (Broadband). Video conference.	Long Term Evaluation (LTE) (Ultra-Broadband). Online Multi-media newspaper and TV prog.
Narrow band analog wireless Network	Narrow band wireless Digital network	Wide band wireless network	Wide band wireless network
Service is provided using Circuit Switching	Using Circuit Switching	Data service uses Packet Switching. Voice calls uses Circuit Switching.	Same as 3G service with faster service rate
Internet connectivity: None	Yes	Yes. Faster compare to 2G	Yes. Faster compare to 3G
Uses following standards: AMPS NMT TACS	Uses following standards: GSM CDMA TDMA	Uses following standards: UMTS CDMA2000	Uses following standards: WIMAX
Data Rate: 14.4Kbps	Data Rate: 144Kbps	Data Rate: 2Mbps Download speed: Up to 42Mbps	Data Rate: 2Mbps to 156 Mbps or higher. Download speed: up to 100Mbps

More the G number is bigger faster we get in internet/data services and online multi-media programs with less latency possible.

Please refer below links for more details on the telephone technology

1G: http://en.wikipedia.org/wiki/1G

2G: http://en.wikipedia.org/wiki/2G

3G: http://en.wikipedia.org/wiki/3G

4G: http://en.wikipedia.org/wiki/4G

Inserting table in blog post in 3 simple steps :)