Why do humans and animals yawn, and what is its purpose?

Yawning is like a brain reset button that helps your head feel fresh and focused.

Think of your brain like a computer that runs hot when you are tired or bored. Just like a laptop needs to cool down, your body uses a yawn to lower brain temperature. You might have noticed yawning when you are sleepy, but it also happens when you are paying attention. It is not just