Question:

 	I was recently perusing the /dev directory on a next
when I came upon the entry /dev/drum.  This seemed a bit odd, I thought
that drum memory went out of fashion long, long ago.  The man pages
didn't have anything to say about drum.  Does any have any insight
on this odd device entry?

Answer:

This actually has nothing to do with drum memory.  It's a part of the
UUCP system.

Long, long ago, even before version 6, somebody wanted to implement a
program to copy files between two machines running Unix.  At the time
there were no modems becuase there weren't even any telephones.  A
Bell Labs researcher who had just visited Africa seized upon the idea
of communicating by beating on drums, as the native Africans did.  He
added a drum interface to his PDP-11 and the device driver was called,
of course, /dev/drum.  Uucp would call a lower level program called
`bang' to activate this device driver.  Messages could also be sent
manually by typing `bang drum' at your shell prompt.  People soon
devised shell scripts that would take a mail message, convert it
appropriately, and call bang to send it.  Soon they were sending
multi-hop messages though several sites this way, which is how the
`bang path' got its name.

With the advancements in communications technology (semaphores in
particular), /dev/drum was removed from UNIX around version 6 or 7, I
believe.  The NeXT developers reinstated it on the NeXT because they
felt that a true multimedia machine should have as many options as
possible.

I hope this explanation helped.