Hopefully you will have seen the recent press around a discovered security vulnerability that affects the Linux operating system or more specifically the BASH shell and systems that make use of that shell. Maybe you saw the pretty cool logo around recently. (Other logos have been floating around too but this is my fave.)
BASH BASH (Bourne Again SHell) is a command processor. It is where you type commands you want to run and the shell takes what you type and interprets it and gives you back an output or does something.