Computer Hardware Blog

RAID - Redundant Array of Inexpensive Disks is used to enhance the speed that the data is accessed or it’s reliability. In a raid configuration, several hard disk drives are connected and configured in such a way to make “one hard drive”.

There are several different kinds of RAID configurations. Here are some of the more commonly used ones:

RAID 0 (Stripe)

This configuration is used for speed and size: two or more hard disk drives are connected in such a way that all information is segregated into logical blocks and saved on different hard disk drives simultaneously. The advantage of this RAID type is that it is larger in the aspects of size and faster in the aspects of speed. The disadvantage with this RAID type is that if one hard disk drive becomes damaged, information on all the hard disk drives connected to this RAID will be lost.

RAID 1 (Mirror)

This configuration is used for reliability: usually, two or more hard disk drives are connected as such that the similar information is saved on all hard disk drives in this RAID. The size and speed of this RAID are the smallest and slowest hard disk drive.

RAID 0+1 (Mirrored Stripe)

This configuration is for speed, size and reliability: usually more than two hard disk drives are connected as one RAID 0, and every single hard disk drive is mirrored as RAID 1. The disadvantage to this kind RAID type is that it requires double as many hard disk drives to get the same speed and size as in RAID 0, but in turn, it is more reliable.

RAID 5 (Stripe with Redundancy)

This configuration is utilized for speed, size and reliability: usually more than three hard disk drives are connected as one RAID, and one of the hard disk drives is used to keep redundancy information. This feature (Redundancy information) enables the ability to restore the RAID if one of the hard disk drives is faulty.

Computer storage devices are used to store data so that it can be accessed later on. One of best examples of a storage device is the hard disk. In the earlier days, hard disks were not the de facto standard part in a personal computer. However, these days you cannot find a personal computer that doesn’t have a hard disk. The technology involved behind hard disks has improved tremendously. 10 years back, it was difficult to find hard disks exceeding a capacity of 2-3 GB, but now hard disks with 250 GB capacity have become very common. This is the way technology has progressed.

RAM i.e. Random Access Memory is another example of a computer storage device. The RAM is where the computer stores the data that is is executing. As the name suggests, data stored in the RAM can be randomly accessed by the microprocessor and that too at a much faster rate when compared to other means of storage like the hard disk.

Other common computer storage devices include the CD, DVD and the USB drive. In servers, tape drives are also used to back up data. Years ago when main-frame computers were in use, tape drives are used extensively. However, now tape drives are no longer popular as other means of mass storage like CDs and DVDs are more advantageous.

In the years to come, computer storage devices will become more and more efficient. Their capacities will also increase tremendously. We are already about to see hard disks with capacities ranging into terabytes (i.e. 1024 GB). Other storage devices like USB disks and optical media are also predicted to go into the terabyte range.