4G is the marketing name for fourth-generation wireless, the current (as of 2020) state of the art in deployed broadband mobile communications. According to the International Telecommunication Union (ITU), a 4G network requires a mobile device to be able to exchange data at 100 Mbit/sec although most technologies branded as 4G do not offer this level of performance.
5th generation mobile wireless broadband networks, with performance loads between 100 and 1000 times that of existing 4G networks. 5G communications are just beginning to be deployed as of 2020. 5G includes support for several different frequency bands with substantially different performance characteristics; some are extremely high speed but extremely short range (10s of gigabits/second bandwidth over ~100 meters), while others offer significant range improvements over existing 4G networks but with lower bandwidths.