How a Power Outage Can Kill Your Hard Drive
Your hard drive uses an array of complex, sensitive devices to store, read, and write data. Those devices—the hard disk platters and the read/write heads—are the most at risk when the hard drive loses power. Obviously, a sudden loss of power is not a situation with a 100% hard drive fatality rate. But when a power outage kills your hard drive, here’s what happens:
When you normally power down your computer, it sends shutoff signals to your hard drive and tells it to suspend its operations. The read/write heads pull away from the platters before the spinning platters come to a stop, and the drive safely powers down.