What is full form of BITnet?

Answer 1

Because It's Time network.

A little background, for those who've never heard of it: BITnet was a network of university mainframes in which universities would pay the bills for a dedicated uplink to one or two "nearby" universities ("nearby" could mean "less than 200 miles away" in some cases). There was a routing table to hint to each computer where all the other computers were connected, so someone at, say, the University of Missouri - Rolla could send messages to someone at, say, Penn State by going through their local mainframe, then to the University of Missouri - Columbia, then to UM - St. Louis, then to the University of Illinois at Urbana-Champaign, then to the University of Illinois at Chicago, and so on down the line until it eventually reached Penn State. Both emails and short text messages could be sent this way; the system was fast enough for an interactive conversation to be feasible most of the time.