Redundant Array of Independent Disks, or RAID, is a method of keeping content on a number of hard disk drives simultaneously. A RAID could be software or hardware depending on the drives which are used - physical or logical ones, yet what’s common between them is the fact that they all perform as just a single unit where info is stored. The main advantage of using a RAID is redundancy because the information on all drives will be the same all of the time, so even in case some drive fails for whatever reason, the data will still be present on the rest of the drives. The overall performance is also better as the reading and writing processes will be split between various drives, so a single one won't be overloaded. There are different kinds of RAIDs where the functionality and fault tolerance can vary according to the exact setup - whether data is written on all of the drives in real time or it's written on a single drive and afterwards mirrored on another, what amount of drives are used for the RAID, etcetera.
RAID in Cloud Web Hosting
The hard disks that we employ for storage with our outstanding cloud web hosting platform are not the traditional HDDs, but high-speed solid-state drives (SSD). They operate in RAID-Z - a special setup created for the ZFS file system that we work with. Any content that you upload to your cloud web hosting account will be held on multiple hard disks and at least one will be employed as a parity disk. This is a special drive where an extra bit is included to any content copied on it. In case a disk in the RAID stops functioning, it'll be replaced without service interruptions and the info will be recovered on the new drive by recalculating its bits using the data on the parity disk plus that on the other disks. This is done so as to guarantee the integrity of the info and along with the real-time checksum validation that the ZFS file system performs on all drives, you will never have to worry about the loss of any data no matter what.