bitblt = B = bits
BITNET /bit'net/ n., obs.
[acronym: Because It's Time NETwork] Everybody's least favorite piece of the network (see the network) - until AOL happened. The BITNET hosts were a collection of IBM dinosaurs and VAXen (the latter with lobotomized comm hardware) that communicate using 80-character EBCDIC card images (see eighty-column mind); thus, they tend to mangle the headers and text of third-party traffic from the rest of the ASCII/RFC-822 world with annoying regularity. BITNET was also notorious as the apparent home of B1FF. By 1995 it had, much to everyone's relief, been obsolesced and absorbed into the Internet. Unfortunately, around this time we also got AOL.
--The Jargon File version 4.3.1, ed. ESR, this entry manually entered by rootbeer277.