n. (also net)
An international telecommunications network that uses the TCP/IP protocol to connect smaller computer networks.
A connection of networks, possibly by means of the Internet.
The Internet1 is not synonymous with the World Wide Web. The latter is a service that is provided using the Internet. The Internet can be used for a variety of other services, including file transfer, telnet, email, and instant messaging. The Internet grew out of Department of Defense research to develop a robust communications system that could withstand significant damage to the physical network, especially damage caused by a nuclear war. That original network was called ARPAnet.
Knowles and Elliott 1997 The abbreviated term internet, uncapitalized, began to be used in the early seventies; it was a shorthand term for the communications circuits and their controlling software which linked together the separate computer networks comprising the US military ARPANET system. By the early eighties, the number of linkages had grown greatly to include many universities and other research bodies; by then the word had gained an initial capital letter, referring to the set of computer systems connected in this way as a single unique entity.
Long 2004 Effective with this sentence, Wired News will no longer capitalize the "I" in internet. ¶ At the same time, Web becomes web and Net becomes net. . . . the decision wasn't made lightly. Style changes are rarely capricious, since change plays havoc with the editor's sacred cow, consistency. ¶ A change in our house style was necessary to put into perspective what the internet is: another medium for delivering and receiving information. That it transformed human communication is beyond dispute. But no more so than moveable type did in its day. Or the radio. Or television.