Hard Disk Drive Is a data storage device used to store and retrieve digital information using disks (discs) coated with magnetic material. Basically, the hard drive functions to store digital data. All data that you store on a computer is on the hard disk. Not just documents, pictures, music and videos. But also your computer's Programs, Preferences, and even Operating Systems are all stored on the computer's hard disk.

If your computer's hard disk is damaged, then you will lose everything. That is the reason most people or companies have a data backup (Data Backup). They have another hard drive and copy all their important files to the hard disk.