I just got a programming assignment, and we are supposed to write it under UNIX OS. I have never used unix in my life... so yea.
Questions Where do I go to install it/ how? I believe I am supposed to use Unix version 3 or something
If I program in Linux, will it work in Unix?
for all intensive purposes linux is unix.
unix is what linux is built on.
you might try looking into ubuntu, it is a very easy to install user friendly version. Good community that can help you out.
note, osx is also unix based )
I've liked ubuntu...Easier to get working than some of the other distributions.
The important question to ask is what language will you be using? Linux is a Unix-like operating system, but isn't binary compatible with other flavors of Unix. So unless you're writing a Java app, a shell script, or a very basic C/C++ application (which would require a recompile, and no non-standard C/C++ library calls), you won't be able to write it on Linux and run it on Unix.