Hyak's default shell is bash which is also the default shell on a Mac computer.
Note that Linux commands and filenames are case sensitive. For example pwd is a valid Linux command. However, if your try to run PWD at the command line then you will get an error "command not found".
Here is a link about the linux command line:
Here is a link to Software Carpentry's lessons on the bash shell, Python, git etc. (Scroll down for videos of their courses.)
Software Carpentry also conducts workshops at UW. See below link for the next workshop at UW: