A hard disk drive (HDD), hard disk, hard drive, or fixed disk is an electro-mechanical data storage device that stores and retrieves digital data using magnetic storage and one or more rigid rapidly rotating platters coated with magnetic material.

What is a disk used for?

Disk storage is now used in both computer storage and consumer electronic storage, e.g., audio CDs and video discs (VCD, standard DVD and Blu-ray). Data on modern disks is stored in fixed length blocks, usually called sectors and varying in length from a few hundred to many thousands of bytes.

What is the role of a hard disk?

A hard drive is the hardware component that stores all of your digital content. Your documents, pictures, music, videos, programs, application preferences, and operating system represent digital content stored on a hard drive. ... Everything stored on a hard drive is measured in terms of its file size.