Striping partitions help spread data over multiple disk drives. Mirroring will copy identical data onto more than one drive. RAID employs the techniques of disk mirroring or disk striping. RAID arrays appear to the operating system (OS) as a single logical drive. Because using multiple disks increases the mean time between failures, storing data redundantly also increases fault tolerance. RAID works by placing data on multiple disks and allowing input/output (I/O) operations to overlap in a balanced way, improving performance. There are different RAID levels, however, and not all have the goal of providing redundancy. RAID (redundant array of independent disks) is a way of storing the same data in different places on multiple hard disks or solid-state drives (SSDs) to protect data in the case of a drive failure.
