A hard disk drive is known as a hard drive, hard disk or fixed disk drive. Hard drives have platters with magnetic surfaces that rotate rapidly. Digitally encoded data is stored on the platters and the hard drive is non-volatile, which means that the data is safe even when the power to the drive is turned off.
Hard disk drives were introduced in 1956 and their popularity in the 1990’s with the need for large-scale storage systems, led to RAID arrays. More recently, hard disk drives have been used in camcorders, digital audio players, ipod, and video game consoles.