computer networking technology used in local area networks (local area network) (LANs).

Ethernet was created in 1973 by a team at the Xerox Corporation's Palo Alto Research Center ( Xerox PARC) in California. The team, led by American electrical engineer Robert Metcalfe, sought to create a technology that could connect many computers over long distances. Metcalfe later forged an alliance between Xerox, Digital Equipment Corporation, and Intel Corporation, creating a 10-megabit-per-second (Mbps) standard, which was ratified by the Institute of Electrical and Electronics Engineers (Electrical and Electronics Engineers, Institute of) (IEEE). In 1979 Metcalfe created 3Com Corporation to commercialize Ethernet. 3Com started by building Ethernet circuit boards for minicomputers before releasing an Ethernet card (plug-in circuit board) for the IBM (International Business Machines Corporation) personal computer (PC) in 1982. This gave PCs the efficiency, convenience, and power of computer networks. The true potential of Ethernet was unleashed in 1990 with the creation of the World Wide Web by British computer scientist Tim Berners-Lee (Berners-Lee, Sir Tim).

Ethernet networks have grown larger, faster, and more diverse since the standard first came about. Ethernet now has four standard speeds: 10 Mbps (10 Base-T), 100 Mbps (Fast Ethernet), 1,000 Mbps (Gigabit Ethernet), and 10,000 Mbps (10-Gigabit Ethernet). Each new standard does not make the older ones obsolete, however. An Ethernet controller runs at the speed of the slowest connected device, which is helpful when mixing old and new technology on the same network.

Many networking standards have been suggested as replacements for Ethernet, the most successful being wireless networking. However, Ethernet is still used in most computer networks because of its low cost, flexibility, and backward compatibility.