Intergalactic Computer Network or Galactic Network was a computer networking concept similar to today's Internet.

J.C.R. Licklider, the first director of the Information Processing Techniques Office (IPTO) at The Pentagon's ARPA, used the term in the early 1960s to refer to a networking system he “imagined as an electronic commons open to all, ‘the main and essential medium of informational interaction for governments, institutions, corporations, and individuals.’” An office memorandum he sent to his colleagues in 1963 was addressed to "Members and Affiliates of the Intergalactic Computer Network". As head of IPTO from 1962 to 1964, “Licklider initiated three of the most important developments in information technology: the creation of computer science departments at several major universities, time-sharing, and networking.”

By the late 1960s, his promotion of the concept had inspired a primitive version of his vision called ARPANET, which expanded into a network of networks in the 1970s that became the Internet.

A computer network or data network is a telecommunications network which allows computers to exchange data. In computer networks, networked computing devices exchange data with each other along network links (data connections). The connections between nodes are established using either cable media or wireless media. The best-known computer network is the Internet.

Network computer devices that originate, route and terminate the data are called network nodes. Nodes can include hosts such as personal computers, phones, servers as well as networking hardware. Two such devices can be said to be networked together when one device is able to exchange information with the other device, whether or not they have a direct connection to each other.

Computer networks differ in the transmission media used to carry their signals, the communications protocols to organize network traffic, the network's size, topology and organizational intent. In most cases, communications protocols are layered on (i.e. carried as data) over other more specific or more general communications protocols, except for the physical layer that directly deals with the transmission media.