RAID (Redundant Array of Independent Disks) is a technology that combines multiple physical disk drive components into one or more logical units for the purposes of data redundancy, performance improvement, or both.
What is RAID?
RAID allows you to store data across multiple hard drives. Depending on the configuration (RAID level), this can protect your data if a drive fails, make your system faster, or both.
RAID 0 (Striping)
Splits data evenly across two or more disks, without parity information, redundancy, or fault tolerance.
RAID 1 (Mirroring)
Consists of an exact copy (or mirror) of a set of data on two or more disks.
RAID 5 (Striping with Parity)
Stripes both data and parity information across three or more drives. It provides a good balance of performance and redundancy.
RAID 10 (1+0)
Combines disk mirroring and disk striping to protect data. It requires a minimum of four disks.
Conclusion
Choosing the right RAID level depends on your specific needs. If speed is everything and data loss isn't a concern, RAID 0 is an option. For critical data, RAID 1 or RAID 10 offers the best protection. For a balance of capacity and redundancy, RAID 5 or 6 are common choices.