07/04/2018
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 call '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 it's powered off.