Why do things heat up like rubbing your hands fast or brakes on a car? How does stuff heat up in general and why is that?

Question

So ive wondered what happens exactly that causes our hands to heat up when you rub them really fast together or why do brakes heat up when used. Why does stuff in general heat up when its put under stress or when its at a high speed and getting slowed down.
Why is it that it all heats up? Why does it not just stay at the same temperature?

Also why do CPU on a PC heat up that much? There is nothing moving in it to make it hot.

In: Physics

Answer 1

Heat is caused by atoms vibrating (and randomly rubbing against each other) by rubbing your hands together you’re (simply put) recreating that process