uucp was the file transfer protocol in athe 1980's which ran on early UNIX computers. System managers would exchange files on computers of other universities and research labs in an early version bulletin boards. Also used to transfer files over a local area network.
If you have not noticed, you can no longer push start a car. And no one uses uucp. But it is still there and accessible. It would behoove you to be aware of its presence and how it works. Hey, there is even a second on using, dare I say “MODEM’s”. There is a good explanation of ttys that some people could use today. The second on xenix makes this a coffee table book.