RAID (redundant array of independent disks) systems consists of 2 or more hard drives connected together which can either appear as one large volume or a mirrored set. Common RAID settings are:
RAID 0 – Data is striped across all disks providing fast read/write, ideal for video editing. The advantage is speed but if one drive fails in RAID 0 you will lose your data so many users prefer RAID 5.
RAID 5 – Data is spread across all disks, if one drive fails, your data is still in tact and accessible.
RAID 1 – Disk 1 is mirrored on to Disk 2. Ideal for real time dual backup.