If you ever played any type of fighting game you've probably witnessed at some point in time that you are mashing every button to improve your chances of winning. The action of button mashing involves quite a bit of physics. For every push down of the button physics in involved, starting with the press of the buttons for each time you push the button down the button applies the same amount of force back onto your finger. That is called the normal force. Every time the button comes back up to its original position it is most likely due to the fact that there is some kind of spring involved. Springs are commonly involved in physics when dealing with forces. Overall I hope you learned something and maybe next time you're playing a fighting game or any type of game that involves the pressing of buttons you'll remember this little reading.