What is RAID and How Does It Work?
RAID stands for Redundant Array of Independent Disks or Redundant Array of Inexpensive Disks - kinda depends on who you ask. The term RAID came into being in 1988 after it was defined in the University of California, Berkeley. The original patent for the concept of RAID however came from within IBM in 1978.
Regardless of the actual meaning or origin of RAID the principles remain the same. RAID offers a way of replicating and protecting data across multiple hard drives. In essence it allows you to keep an exact replica copy of your data on a completely separate hard drive. In the case that your primary hard drive fails then the secondary RAID disk takes over and you can continue working. RAID simply allows you to use several different drives but as far as you're concerned you'll only see one single drive present - this of course depends on the RAID level you wish to use (RAID 0 to RAID 6).
For many years RAID was only ever used on high end servers where data redundancy was critical. Modern home computers are now featuring RAID capabilities by default - home processing power has come to the point where it can support RAID functionality.