Explain how information is stored magnetically on hard drives?

Question

Explain how information is stored magnetically on hard drives?

Answer 1

Mechanically, it operates slightly similar to vinyl players of the past, an arm constantly moves inward and outward from the center of a spinning round platter. The platters themselves are not magnetic, but are coated with a magnetic material, than can be as thin as 3 atoms (fascinating :O).

The "needle" or "arm" part if you will, has the ability to change small parts of the disc to charged or not charge. (1 or 0), hence why a low level format reduces a drive to a complete zero state.

In the true model, hard drives have multiple arms and platters in them.

My knowledge is slightly lacking, so don't take this as a direct quote, but view the sources for a better understanding.

Answer 2

The science of magnetism is complex. But if you've ever fooled around with a magnet and some nails, you'll know that the technology—the science in action—is quite simple. Iron nails start off unmagnetized but, if you rub a magnet back and forth over them, you can make them magnetic so they stick to one another. Magnetism has some simple, practical uses. For example, junkyards use electromagnets (huge magnets that can be switched on and off using electricity) to pick up and move around piles of metal scrap.

Magnetism has another very important use. Suppose you need to leave a message for a friend and all you have is a magnet and an unmagnetized iron nail. Suppose the message is a very simple one: either you will see your friend later that day or not. You could arrange with your friend that you will drop a nail through their letterbox. If the nail is magnetized, it means you will see them later; if the nail is unmagnetized, you won't. Your friend gets in from school and finds a nail on the doormat. They take it to the kitchen table and try to pick up a paperclip. If the clip attaches to the magnet, it must be magnetized—and it must mean you plan to see them later. It's a pretty weird way to leave a message for someone, but it illustrates something very important: magnetism can be used to store information.

check this link to know more about how hard drives works: http://www.explainthatstuff.com/harddriv...