RAID 0:

• Performance-driven level. 
• Stripes data across the drives to combine total read/write speed.
• Doesn’t protect against drive failure.

RAID 1:

• Backups data on each disk.
• Slower than others.

RAID 5:

• Stripes data to 3 drives minimum.
• Parity data in all drives.
• Less chance of failure.

RAID 6:

• Stripes data to >4 HDDs.
• Double parity.
• You can afford two HDD failures without data loss.

RAID 10:

• Requires at least 4 HDDs.
• Combined read speed of entire drives and write speed of half of them.
• Better writing speed in smaller arrays.

RAID 50:

• Combination of multiple RAID 5s with RAID 0.
• Combined read speed of all drives and write speed of the raid 5s combined.
• One drive failure in each RAID 5 can be tolerated.

RAID 60:

• RAID 6s with RAID 0 combined.
• Combined read speed of entire drives and write speed of individual raid 6s.
• You can afford two drives fail in each RAID 6 without data loss.