The following table provides an overview of some considerations for standard RAID levels.

Level Description Minimum number of drives Space efficiency Fault tolerance Read performance Write performance
RAID 0 Block-level striping without parity or mirroring 2 1 None n× n×
RAID 1 Mirroring without parity or striping 2 1/n n − 1 drive failures n× 1×
RAID 2 Bit-level striping with Hamming code for error correction 3 1 − 1/n log2 (n − 1) One drive failure Depends Depends
RAID 3 Byte-level striping with dedicated parity 3 1 − 1/n One drive failure (n − 1)× (n − 1)×
RAID 4 Block-level striping with dedicated parity 3 1 − 1/n One drive failure (n − 1)× (n − 1)×
RAID 5 Block-level striping with distributed parity 3 1 − 1/n One drive failure n× (n − 1)×
RAID 6 Block-level striping with double distributed parity 4 1 − 2/n Two drive failures n× (n − 2)×
RAID 10 Block-level striping on top of two RAID0 4 1/2 1 drive failure nx 1

 

More detail see Standard RAID levels