* RAID 0

Data is written/read across two or more drives simultaneously, effectively allowing it to be accessed much more quickly. It allows all the hard drives in the RAID array to appear as a single device with the total combined storage of all the drives. E.g. two hard drive of 256GB and 512GB, would appear as a single 768GB drive. This form of RAID is sometimes called striping and does not provide any extra redundancy than storing your data to a single hard drive. If one drive fails and is then replaced, the other can not rebuild the whole data file.