Hard drive
The Hard Disk Drive stores data on a number of rapidly rotating disks. Each disk is coated with a magnetic material known as a platter. The arm over the disk is also fitted with a magnetic tip. This allows the head to be moved to the magnetic interference detected. This storage device can hold data even when shut down. The arm holds magnetic patterns to the disk, which is its way of writing data. The data on a hard disk drive can be easily changed or erased as they are magnetic signals and not physical imprints. A hard drives function is to read from and write to a hard disk.