Identification friend or foe

Identification friend or foe (IFF) is like playing a game of "tag" with your friends. You know who your friends are, so when you play tag you don't tag them. But, when you see someone who isn't your friend, you get to tag them because you don't know them.

Now imagine if you were playing tag, but with airplanes! When planes fly around, they also need to know who is their friend and who is their foe. They don't tag each other, but instead they communicate with each other using special codes.

These codes help planes to know if the other planes in the sky are their friends or not. If a plane doesn't know the code, they might think the other plane is an enemy and try to shoot it down. But, if they do know the code, they know the other plane is their friend and they won't try to shoot it down.

So, IFF is like a game of tag but with airplanes, and instead of tagging, they use special codes to make sure they only interact with their friends and not their foes.