HARD DISC
What is Hard Disk Drive( HDD) A hard disk drive ( HDD ), hard disk , hard drive or fixed disk 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. 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.