RAID is the logical combining of two or more drives into an 'array' which, depending on the array you have specified will serve a particular purpose.
RAID 0 combines usually two drives into one logical drive. This gives increased performance, but lacks redundancy.
RAID 1 Usually two drives again, one mirrors the other for data integrity. Max redundancy for a slight loss of performance.
RAID 0+1 combines both above, but requires 4 drives.
Other forms of RAID exist, and I'm sure Toey or some other helpful soul will provide links. Bottom line is RAID = more drives = more cost.
As to the hotswap stuff, I believe that's RAID...5? Hmmm. Not sure. Tends to be for server usage. Another rule...the more secure and convenient it is, the more expensive it is.
<b><font color=blue>~ Whew! Finished...Now all I need is a Cyrix badge ~ </font color=blue>
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