RAID 0, RAID 1, RAID 5, RAID 10 Explained

RAID stands for Redundant Array of Inexpensive (Independent) Disks.

These are some of the RAIDs which are mostly used.

RAID 0
RAID 1
RAID 5
RAID 10

RAID 0 

• Blocks are stripped
• Excellent performance  (Blocks stripped)
• No redundancy (No mirror no parity)
• Cannot be used for critical system

RAID 1

• Mirrored data to both drives
• Minimum 2 disks
• Good performance(No stripping no parity)
• Excellent redundancy(blocks mirrored)

RAID 5

• Minimum 3 disks.
• Good performance ( as blocks are striped ).
• Good redundancy ( distributed parity ).
• Best cost effective option providing both performance and redundancy. Best for DB that is heavily read oriented. Write operations will be slow.

RAID 10

• Minimum 4 disks.
• This is also called as “stripe of mirrors”
• Excellent redundancy ( as blocks are mirrored )
• Excellent performance ( as blocks are striped )
• If you can afford the dollar, this is the BEST option for any mission critical applications (especially databases).