What is Bash?
Bash, or the Bourne Again SHell, is based on the Bourne shell. It is the default shell command language interpreter for GNU Linux/Unix and is accessed via a terminal. The shell was the original method for interacting with the operating system before GUIs were implemented. It has the ability to execute single commands, understand regular expressions, as well as scripts written in the bash language. It is currently the default interactive shell on most all modern Linux distributions.