raid 0, (stripping) it takes half of one file puts on one hard drive, and then half of there other file on the other hard drive which equals performance, but if one drive goes bad then the other one is bad also. raid 1 is mirroring it puts the exact samething on both drives so if one goes bad then you still have the other one. there is raid 5 where you need 3 harddrives stripping with parity, that means you get stripping peformance but if you lose one drive you still won't lose anything.