Electronic Mail (e-mail) -- a way of sending a message to a specific person or groups of people, much like you would send a postcard or letter to a specific address. You can send e-mail to anyone who has an e-mail address.

Ethernet -- a network protocol that is able to send data at 10 Mbits/second. This is a very common method of networking computers in a local area network. The Ethernet protocol allows a host computer to exchange information with its users.

Exchange -- a geographic boundary within which a telephone company is allowed to provide local service.