Ethernet
Ethernet is the family of IEEE 802.3 standards for wired local and access networks, defining both the cabling and signalling and the format of the frames sent over it.
What is Ethernet?
Developed at Xerox in the 1970s, Ethernet started on shared coaxial cable and now runs over twisted-pair copper and fibre, at speeds from 10 Mbit/s up to 400 Gbit/s and beyond. Its frame format and MAC addressing sit at layer 2, while its cable and signalling specifications sit at layer 1. Operators also sell Ethernet as a carrier service (Ethernet leased lines, sometimes called Ethernet as a service).