This picture shows the insides of a hard disk drive. In this drive, the disks are 3.75" in diameter (there is a stack of two). The read/write head is the tiny rectangle on the end of the seek arm (there are four heads in this drive, on the top and bottom of each disk).

Hard disk drives are sealed to prevent dust from entering. The space between the read/write heads is smaller than the size of a dusk particle, so dust can ruin the disk. (The drive was defective, so we opened it up for fun.)

Close this window when finished.