In-band full-duplex (IBFD) technique has emerged as an attractive solution for increasing the throughput of wireless communication systems and networks. With IBFD, a wireless terminal is allowed to transmit and receive simultaneously in the same frequency band. This paper reviews the main concepts of IBFD wireless. In this article we will focus on the following question: What is IBFD? Why is IBFD important now? And, the influence of IBFD on the throughput of Transmission Control Protocol (TCP)