Hard Disk Drive

computer storage · magnetic · technology

Spinning platters store data. Inside a hard disk drive are thin, circular disks called platters that spin really fast, sometimes thousands of times per second. Magnetic coating on these platters holds all your photos, videos, and documents like a high-speed filing system.

Magnetic heads read everything. Tiny magnetic reading and writing heads hover just above the spinning platters without touching them, kind of like how a record player needle works. These heads can find and grab any piece of data in any order, which is why computers are so quick at finding your files.

Data stays when off. Hard disk drives are non-volatile, meaning they remember everything even when you turn off your computer and unplug it. That's why all your games and photos are still there the next day.

Compact but powerful. Modern hard drives fit in a small rectangular box, much smaller and lighter than the massive disk drives from the 1960s and 1970s, yet they can store thousands of times more information.

Random access anywhere. Hard disk drives can grab data from anywhere on the platter in any order, so it doesn't matter if your favorite song file is stored in the front, middle, or back, your computer finds it just as fast.