If you, or some of the software that you deal with, work in a terminal, you'll have some value of $TERM set. If you use a terminal emulator which isn't one of t

If you, or some of the software that you deal with, work in a terminal, you'll have some value of $TERM set. If you use a terminal emulator which isn't one of the classic hits (eg xterm or rxvt), or if you use a terminal mux like screen or tmux, you'll want to have an entry in your terminfo database which describes the terminal accurately, so that simple things like backspace and delete work correctly, or snazzy stuff like 256 color support. So having some kind of general understanding of what terminal capabilities are, how they're expressed in termcap and terminfo, is helpful. In particular, I think having an understanding of the kinds of things that can go wrong in a terminal, for example if you've ever ran cat with a binary file to stdout, is very helpful. It's not the sort of topic you need to spend a lot of time studying, but if you're a UNIX user, I think its a good idea to consider it part of the canon.