Mac OS X - Terminal
For Mac OS X can access the command prompt through a program called Terminal.
How do find it?
In Mac OS X you can find any application using the search spot light:
Click on the magnifying glass icon
Then type in “terminal” and you should see something like:
Click on the top icon and you should be able to access the terminal.
It’s not the only way to access an application - but hopefully this will have gotten you started.