RAID, or Redundant Array of Independent/Inexpensive Disks, is a way of storing information. It uses multiple hard drive disks and hence offers greater protection of your data as well as higher performance. It has several levels with slightly different mechanisms and features, all running on the logic that a line of inexpensive disks can be more effective than one very expensive disk. The main levels are RAID 0, RAID 1 and RAID 5
RAID 0 was the first RAID design made. It stripes, which means it breaks data up into pieces and writes them across drives. This means that the information that can be transferred at any given time is higher, so computers will run faster. RAID 0 is perfect for professionals that use really big files and need really fast speeds — like if you’re a music production engineer or graphic designer working on massive files. However, RAID 0 has an issue in that if one drive fails you lose the ability to use any other drive on the system. It’s not quite the end of the world scenario as it would be if your hard drive completely died, as companies like Secure Data Recovery boast a RAID recovery success rate of over 96%.
RAID 1 is what most people think of when they first get into their RAID arrays. RAID 1 requires at least 2 disks and it mirrors data so you have several disks that contain the same information. This means that if one disk goes down, you have others to back it up, but you would need to buy another disk which can be expensive if you’re working in terabytes. When you’re using RAID 1, your writing speeds can be affected as data needs to be written to several disks at the same time. This means if you have several disks of different qualities, you will work only as fast as the slowest one of the bunch. You should get a RAID 1 if you don’t like to regularly back up your drive and if you’re terrified of drive redundancy and prefer to be secure over having a fast performance.
RAID 5 tries to combine the performance of RAID 0 with the security of RAID 1. It stripes data across all drives in the array but also spreads what’s known as parity data. Parity data is crucial for the backup process and helps to ensure that if one drive fails your whole array won’t go down with it. However, RAID 5 ensures that writing parity data doesn’t cause the same slowdown as with RAID 1 as it spreads it across all drives. This is a very powerful solution and is the basis for other more nuanced RAID systems like RAID 6 (which uses 2 disks for parity and correction so you can recover data more safely).
The start-up cost for a good RAID array is lower than it ever has been due to Moore’s Law’s effects on storage costs. Basically, everybody should use a RAID array as an excellent backup solution, especially if you’re a hobbyist working with a lot of large files that require an increase in speeds.