RAID is the organization of multiple disks into a large, high performance logical disk.
Data striping also results in uniform load balancing across all of the disks, eliminating hot spots that otherwise saturate a small number of disks, while the majority of disks sit idle. A disk array with a hundred disks is a hundred times more likely to fail than a single disk. The solution to the problem of lower reliability in disk arrays is to improve the availability of the system. This can be achieved by employing redundancy in the form of error-correcting codes to tolerate disk failures. A redundant disk array can now retain data for much longer time than an unprotected single disk.