Hard Drive
The hard drive in a computer acts as a permanent data storage. It can also be reffered to as a hard disk drive. The hard drive is the holder of the hard disk where all of the computers physical files and folders are kept. When data is sent to and from the hard drive it is processed by the disk controller. The disk controller is what tells the hard drive what to do.
Most hard drives are internal but there are external hard drives avaliabe. These can act as a backup or give more data to the owner. External hard drives come in a lot of different sizes.