A computer network consists of two or more computers and other devices connected to each other so they can share physical and logical resources, these can be of type: data, printers, messages (emails), among others.
The Internet is a comprehensive communication system that connects many networks of computers. There are ways and means of several devices that can be connected and shared by means of access, protocols and security requirements.
The media can be: telephone, cable, satellite or wireless (wireless).
The purpose of networking is to allow the exchange of data between computers and the sharing of hardware resources and software.
Before the advent of computers equipped with some type of telecommunications system, communication between machines and calculators old computers was performed by human users by loading instructions between them.
In September 1940, George Stibitz used a teletype machine to send instructions for a problem set from his Model K at Dartmouth College in New Hampshire for your calculator New York and received results back by the same means. Connect output systems like teletypes to computers was an interest at the Advanced Research Projects Agency (ARPA) when, in 1962, J. C. R. Licklider was hired and developed a working group which he called the "Intergalactic Network", a precursor to the ARPANET.
In 1964, researchers at Dartmouth developed the Time Sharing System for distributed users of Dartmouth large computer systems. In the same year, at MIT, a research group supported by General Electric and Bell Labs used a computer (DEC's PDP-8) to route and manage telephone connections.
During the 1960s, Leonard Kleinrock, Paul Baran and Donald Davies independently conceptualized and developed network systems which used datagrams or packets that could be used in a packet switching network between computer systems.
In 1969, the University of California at Los Angeles, SRI (in Stanford), University of California at Santa Barbara and the University of Utah were connected with the beginning of the ARPANET network using circuits of 50 kbits / s.
Computer networks and the technologies needed to connect and communicate through and between them continue to lead the industry in computer hardware, software and peripherals. This expansion is mirrored by growth in the numbers and types of users of networks from the researcher to the home user.
Today, computer networks are the core of modern communication. The scope of communication has increased significantly in the 1990s and this boom in communications would not have been possible without the progressive advancement of computer networks.