(TCP) The most common transport layer protocol used on Ethernet and the Internet. It was developed by DARPA.
TCP is built on top of Internet Protocol (IP) and is nearly always seen in the combination TCP/IP (TCP over IP). It adds reliable communication, flow-control, multiplexing and connection-oriented communication. It provides full-duplex, process-to-process connections.
Defined in STD 7, RFC 793. It is connection-oriented and stream-oriented, as opposed to User Datagram Protocol.