In 1959, Christopher Strachey filed a patent application for time-sharing and John McCarthy initiated the first project to implement time-sharing of user programs at MIT.
The modem allowed digital data to be transmitted over regular unconditioned telephone lines at a speed of 110 bits per second (bit/s). It was the first commercial modem for computers, released by AT&T Corporation in 1958. military Semi-Automatic Ground Environment (SAGE) radar system using the Bell 101 modem.
The nodes of a computer network may include personal computers, servers, networking hardware, or other specialised or general-purpose hosts. These interconnections are made up of telecommunication network technologies, based on physically wired, optical, and wireless radio-frequency methods that may be arranged in a variety of network topologies. The computers use common communication protocols over digital interconnections to communicate with each other. A computer network is a set of computers sharing resources located on or provided by network nodes.