1. What does RAID stand for?
RAID (Redundant Array of Independent Disks) is a storage technology that combines multiple disk drive components into a logical unit. Data is distributed across the drives in one of several ways called "RAID levels", depending on what level of redundancy and performance (via parallel communication) is required. Marketers representing industry RAID manufacturers later attempted to reinvent the term to describe a redundant array of independent disks as a means of dissociating a low-cost expectation from RAID technology. RAID is now used as an umbrella term for computer data storage schemes that can divide and replicate data among multiple physical drives. The physical drives are said to be in a RAID array, which is accessed by the operating system as one single drive. The different schemes or architectures are named by the word RAID followed by a number (e.g., RAID 0, RAID 1). Each scheme provides a different balance between two key goals: increase data reliability and increase input/output performance.

2. When would we use RAID?
RAID is extremely useful if reliability and data redundancy are important to you. Even if you take backups, you will need to take the time to restore those backups and those backups could be hours or days old, resulting in data loss. RAID allows you to survive a drive loss without data loss and in many cases without any downtime. RAID is also useful if you are having disk IO issues, where applications are waiting on the disk to perform tasks. Going with RAID will provide you additional throughput by allowing you to read and write data from multiple drives instead of a single drive.

3. Define the types of RAID
RAID 0 - Never, unless the data has no value to you.
RAID 1 - (Mirroring) - RAID 1 is generally used with a pair of disks. Those disks would identically mirror/copy the data equally across all the drives in the array. The point of RAID 1 is primarily for redundancy. If you completely lose a drive, you would still stay up and running off the additional drive(s).

RAID 5 - (Striping + Distributed Parity) - RAID 5 requires the use of at least 3 drives and will take the idea of RAID 0, striping the data across multiple drives to increase performance, but also adds the aspect of redundancy by distributing parity information across the disks. With RAID 5 you can lose one disk and still maintain your operations and data.
RAID 6 - (Striping + Distributed Parity) - RAID 6 requires the use of at least 4 drives and will take the idea of RAID 0, striping the data across multiple drives to increase performance, but also adds the aspect of redundancy by distributing parity information across the disks. With RAID 6 you can lose two disks and still maintain your operations and data.

4. Why is RAID 0 of any use if it offers no redundancy?
This will greatly increase speeds, as you're reading and writing from multiple disks at a time. An individual file can then use the speed and capacity of all the drives of the array. The downside to RAID 0 though is that it is NOT redundant; the loss of any individual disk will cause complete data loss.

5. Why do I think RAID 1 could be the most expensive?
Relatively high due to redundant drives; lowest storage efficiency of the single RAID levels. Duplexing is still more expensive due to redundant controllers. On the other hand, no expensive controller is required, and large consumer-grade drives are rather inexpensive these days, making RAID 1 a viable choice for an individual system.
Why would people utilize it if it’s so costly?
RAID 1 offers excellent read speed and a write-speed that is comparable to that of a single disk. In case a disk fails, data do not have to be rebuild, they just have to be copied to the replacement disk

6. As a home computer user, what form of RAID would I chose and why?
Most "regular PC users" do not need RAID, and the extra cost of one or more additional hard drives is usually not justified. Users are typically setting up RAID solely for performance reasons, and choose RAID 0. Unfortunately, RAID 0 just doesn't improve performance all that much for the way a typical PC is used.

7. What is the difference between software RAID and hardware RAID?
Software RAID is the cheaper option, as it does not require a separate hardware RAID card. With software RAID, you are not going to get the additional benefit of the cache and the dedicated processor on a hardware RAID card, these processes will instead take up resources on the processor for the system. If looking to gain additional redundancy with RAID 1, software RAID is a good, cheap option, but if looking to also gain performance, it would highly recommend spending the money on hardware RAID. It is generally not recommended to use a Windows software RAID, as it can often cause various issues. It is recommend going with hardware RAID on a Windows based system.