Define HARD DISK

HARD DISK:

Stores large quantities of data for use at a later time. Uses a HARD DISK CONTROLLER to connect hard disk to motherboard. 

 

Hard Disk Drive

MFM and RLL drives:

Typically have separate controllers and hard disks. RLL controllers can store up to 30% more data on the same disk than MFM controllers. Uses 34-pin AND 20-pin cables to transmit data.

IDE Drives:

Have hard disk controller and hard disk in ONE unit; slightly more difficult to install additional hard disks to IDE systems. Uses 40-pin ribbon cable to transmit data.

SCSI drives:

Uses separate controllers, like MFM & RLL drives, but can transfer data at a much faster rate. SCSI drives are also more expensive. Uses 50-pin or  68-pin cable to transmit data.