This document discusses 4G networks and their evolution. It defines 4G as the next generation of high-speed mobile technologies replacing 3G. Key requirements for 4G include being based on an all-IP packet switched network with peak data rates up to 100Mb/s for high mobility and 1Gb/s for low mobility. The main 4G network types are WiMAX and LTE. Benefits of 4G include faster speeds and better streaming capabilities. The document outlines the growth of 4G globally and its current limited availability in India. Both advantages like increased connectivity and disadvantages like high costs are discussed.