First, let me say what bash is not
Bash is not the cmd.exe app on Windows. That is the DOS shell, which will be further referred to as "The crap shell".
Bash has a history
In 1977 the Bourne shell was introduced. It was a way to get things done with text commands. At the start of the GNU project, Richard Stallman and whoever else was helping decided they wanted to make their own open-source shell, which was based on the Bourne shell, called the Bourne Again SHell-- bash. Kind of a joke on his name.
Now, here's how to use bash.
If you're on a Mac, awesome, as you have it already. Go ahead and open the "Terminal" app. If you're on Windows, you're out of luck. On Linux, bash should be called "Terminal" or "Terminal Emulator".
First, try the command "ls". It should list all the files in your home folder. Now, try the command "mkdir new_folder". This stands for "Make Directory", and we gave it the name to use, "new_folder". Now, try "cd new_folder". It should Change Directories to that folder. I'm not the best at explaining this myself, so here's a better tutorial. http://youtu.be/x73WTEltyHU
