Unix -- the "root" operating system that was created in 1973
               by Thompson and Ritchie

System V
BSD

Linux   --   named after Linus Torvolds in 1992

     distributions:   Ubuntu, CentOS


1.  How to connect your computer to a Linux server
2.  How to logon

MacOS:  https://www.youtube.com/watch?v=aKRYQsKR46I
        the terminal app, go to spotlight search bar and typing "terminal"

Windows:   Putty
        download from   putty.org

In MacOS:  terminal opens into a Unix world on your Mac!  MacOs is form of Unix.
        But even though you have your own Unix world in your machine, you still need to
        connect to the school's server.  
   $ ssh -l rmmeyer brahe.canisius.edu