"Look on my works, ye Mighty, and despair!" -Percy Bysshe Shelley Welcome to the internet. Try not to touch anything.
The internet has amassed a ridiculous number of nicknames that are mostly used by people who don't understand what the internet is. World wide web, internets, information superhighway, intertubes or tubes (popularized after U.S. Senator Ted Stevens famously explained that the internet was not a delivery truck but a "series of tubes") can be thrown around but they all mean the same thing, mostly.
Internet is probably the best term, since at it's most basic level the internet is computers connected to computers. Originally, it was conceived as a way for professors at different universities to share information. Then they let non-PhD's use it and it immediately went downhill.
A map of the internet. If you look real hard, you can see the tubes.
The modern internet is a staggeringly complex conglomeration of communication, media, commerce and a heapin' helpin' of debauchery. The histroy of the internet is full of unknowns, guesses and contradictions, all of which can be found below, according to whatever wikipedia articles were the easiest to plagerize.