Before the current iteration of the Internet, long-distance networking between computers was first accomplished in a 1969 experiment by two research teams at UCLA and Stanford. Though the system crashed during the initial attempt to log in to the neighboring computer, the researchers, led by Leonard Kleinrock, succeeded in creating the first two-node network. The experiment was also the first test of “packet switching,” a method of transferring data between two computer systems. Packet switching separates information into smaller “packets” of data that are then transported across multiple different channels and reassembled at their destination. The packet-switching method is still the basis of data transfer today. When you send an email to someone, instead of needing to establish a connection with the recipient before you send, the email is broken up into packets and can be read once all of the packets have been reassembled and received.
Cerf and Kahn developed a set of guidelines for data transfer using packet switching in 1980, calling those guidelines TCP/IP, or Transmission Control Protocol and Internet Protocol. The TCP part of the protocol is in charge of packing the data before it moves across the network and unpacking it once it has arrived. The IP component acts as the trip coordinator and maps the movement of information from its start point to its end point. While Kleinrock’s experiment proved that a single network between two computer systems was possible, Cerf and Kahn’s TCP/IP provided the backbone for an efficient and large web of interconnected networks—thus the name “Internet.” Though other protocols were developed and used before TCP/IP, such as the file transfer protocol (FTP) and network control protocol (NCP), the Internet as we know it today is built on the basis of Cerf and Kahn’s “network of networks.”