4G stands for Fourth-Generation, In wireless communications it is a totally revolutionary term . You all familiar with 3G technology but 4G is more enhance than 3G,it will also use IP packets to send the data in different formats like voice text ,image etc. but at a much enhanced data rate.
As time changes newer technology replace older one as happened with wireless technology,i.e. first generation is replaced by second generation, second with third one and now scientist are doing research for the replacement og enhanced 3G technology also , fourth generation cannot be an incremental evolution of current 3G technologies, but rather the total replacement of the current 3G networks and handsets. The international telecommunications regulatory and standardization bodies are working for commercial deployment of 4G networks roughly in the 2012-2015 time scale. At that point it is predicted that even with current evolutions of third generation 3G networks, these will tend to be congested.
So how 4G is special ? 4G technology is like total replacement of 3G network because of enhance data rate provided by 4G network.4G can provide a data rate of 100Mbit/s to 1GBit/s speed with premium quality and high sequrity.
4G is being developed to accommodate the quality of service and rate requirements set by forthcoming applications like wireless broadband access, MMS, video chat, mobile TV, HDTV, Digital Video Broadcasting and service like voice and data, and other streaming services for anytime-anywhere.