Hard disk drive
Edit Watch this page Read in another language Hard disk drive "Hard drive" redirects here. For other uses, see Hard drive (disambiguation) . A hard disk drive ( HDD ), hard disk , hard drive or fixed disk [b] is a data storage device that uses magnetic storage to store and retrieve digital information using one or more rigid rapidly rotating disks ( platters ) coated with magnetic material. The platters are paired with magnetic heads , usually arranged on a moving actuator arm, which read and write data to the platter surfaces. [2] Data is accessed in a random-access manner, meaning that individual blocks of data can be stored or retrieved in any order and not only sequentially . HDDs are a type of non-volatile storage , retaining stored data even when powered off. [3] [4] [5] Hard disk drive Internals of a 2.5-inch SATA hard disk drive Date invented 24 December 1954 ; 63 years ago [a] Invented by IBM team l