What is the best available file shredder AND HOW DOES IT WORK?

IM DEAD SERIOUS WHEN I SAY I WANT TO KNOW HOW THE FUGGIN THING "DELETES" THE FILES. I WANNA FUGGIN KNOW HOWWW IT WORKS AND AS WELL COMPARED TO HMMMM LETS SAY A GODDAMM ELECTROMAGNET OR OR THE RECYCLE BIN OR OTHER ALTERNATIVE DELETION METHODS. I swear i will give you as many points as i possibly can, i don't care, I REALLY JUS WANNA FURTHER MY POTENTIAL IN KNOWING AND UNDERSTANDING THE WORKINGS OF A COMPUTER AND ALL IT FUNCTIONS AND COMPONENTS!!