RAID | Redundant Array of Independent Disks

RAID is the acronym for either ‘redundant array of inexpensive disks’ or ‘redundant array of independent disks’.  When first conceived at UC Berkley the former was the actual term that was coined but the latter is more commonly used today intentionally to disassociate the technology from the word inexpensive and the perception that RAID somehow implies a low cost solution.

RAID is a storage technology that provides increased data reliability through data redundancy.  This is achieved primarily by duplicating data across several storage drives in a configuration referred to as an array of disks.

There are several different types of RAID array configurations each type being denoted by a single digit numeral, 0 through 6 (and various combinations thereof).  These types are commonly referred to as RAID ‘levels’.

The makeup of the different RAID levels is varying combinations of redundancy, spanning, mirroring and striping.