The Orthogonal Frequency Division Multiplexing (OFDM) is an important aspect of multicarrier digital data transmission system where a single data stream is transmitted into a several number of lower rates subcarrier signals. This kind of new standard of transmission of data is the first one to perform with OFDM in data packet based communication system. In wireless communication network, the abstraction of parallel transmission of data symbols is implemented to attain high throughput and effective transmission quality. The OFDM is a method to deal with parallel transmission. In this text book, there are five different types of the techniques has introduced to strengthen the communication quality and capacity.