Directory structure on *nix machines

One of the most confusing things when doing basic server maintenance or troubleshooting on a remote machine is where everything is located. A basic understanding of the Filesystem Hierarchy Standard is helpful - though there are, of course, exceptions all over the place, and the standard isn't always consistent! The main directories you'll probably be interested in are:

Finding the Desktop from Bash

MacOS

/Users/YOURUSERNAME/Desktop

or

~/Desktop

Windows (Ubuntu):

/mnt/c/Users/YOURUSERNAME/Desktop

Windows (Cygwin):

/cygdrive/c/Users/YOURUSERNAME/Desktop

Linux

/home/YOURUSERNAME/Desktop

or

~/Desktop