the network n. 1. Historically, the union of all the major
   noncommercial, academic, and hacker-oriented networks, such as Internet,
   the pre-1990 ARPANET, NSFnet, {BITNET}, and the virtual UUCP and
   {Usenet} `networks', plus the corporate in-house networks and commercial
   time-sharing services (such as CompuServe, GEnie and AOL) that gateway
   to them. A site is generally considered `on the network' if it can be
   reached through some combination of Internet-style (@-sign) and UUCP
   (bang-path) addresses. See {Internet}, {bang path}, {{Internet
   address}}, {network address}. 2. Following the mass-culture discovery of
   the Internet in 1994 and subsequent proliferation of cheap TCP/IP
   connections, "the network" is increasingly synonymous with the Internet
   itself (as it was before the second wave of wide-area computer
   networking began around 1980).

  3. A fictional conspiracy of libertarian hacker-subversives and
   anti-authoritarian monkeywrenchers described in Robert Anton Wilson's
   novel "Schro"dinger's Cat", to which many hackers have subsequently
   decided they belong (this is an example of {ha ha only serious}).

   In sense 1, `the network' is often abbreviated to `the net'. "Are you
   on the net?" is a frequent question when hackers first meet face to
   face, and "See you on the net!" is a frequent goodbye.


Source: The Jargon File