TCP/IP, which stands for Transmission Control Protocol/Internet Protocol, is a suite of protocols built into the Unix operating system and is the standard used to connect computers over the Internet. The term TCP/IP actually refers to a whole family of protocols, of which TCP and IP are just two. TCP and IP were first developed in the 1970s in connection with a United States Department of Defense (DoD) research project to connect numerous separate networks designed by different companies into a network of networks, the ARPAnet, named for the DoD's Advanced Research Projects Agency (ARPA).

Tracing the history of TCP/IP therefore leads back to the inception of the Internet. TCP as a suite of communications protocols providing end-to-end network communication was first proposed and implemented in 1974 throughout the ARPAnet, which formed the core of the modern Internet. The emergence of packet-switching technology...