Redundand Array of Independent Disks, Level 1

RAID1 is a hard disk drive array assembled to increase storage reliability. This system automatically copies, through hardware, all data sent to one hard disk drive to another hard drive. If the first hard drive fails, the second disk, which has a backup of all data stored in the first disk, enters in action automatically. This system is also known as mirroring.

In order to work this system needs at least two hard disk drives.