Ethernet provides a broadcast access network for multiple devices to communicate electronically.
It includes a physical specification for media access, access control rules for communication over the link layer, and a data frame format for packets. There are no hard gaurantees that any node will be able to ever transmit it's data. In terms of the ISO standard 7-layer network model, Ethernet Media corresponds to the ISO Physic Layer, and the Ethernet Link Layer and Media Access Protocols correspond to the ISO Data Link Layer. Ethernet is commonly associated with those popular protocols built on top of it.