Idempotent of a code

Idempotence of a code means that no matter how many times you run it, it will produce the same result. It's like pressing and releasing the same button on a remote control over and over again. The TV will only turn on the first time you press the button, and the other times nothing will happen because it is already on. Running a code that's idempotent is like pressing the same button multiple times - the code will only do what it's supposed to do one time, no matter how many times it is run.