Hardware Components

Storage Devices

The two main questions about any computer have to do with how fast it is and how much information it can store. The storage devices determine the storage capacity and can vary widely between each device. Early computers, after punch cards, stored their information on magnetic tape drives, similar but much larger than a car audio cassette tape. The tape drive today is capable of storing huge amounts of information and is used typically to backup a hard drives or databases. Unfortunately, the huge capacity of the tape drive is inconvenient because the information is stored along one continuous strip around a reel. The time it would take to for the tape drive to fast forward to the end of the tape to recall a piece of information then rewind back to the beginning in typical computing functions is unacceptable. This constant back and forth motion will also eventually damage the tape and cause the information to be lost.

As the demands of the computer changed not only did the amount of stored information need to increase but it needed to become smaller and more efficient to access. The floppy drive is very similar to a tape drive. Instead of a long tape the floppy's information is on a floppy magnetic disk of similar material inside a shell. If a tape for a tape drive were around the reel laying flat on the table all the information is wrapped around in nearly concentric circles, with a floppy drive rather than storing that on the width of a tape and passing it through a reader, the information is stored on the circular surface. While the surface is spinning an arm moves to the point on the reel where information that is requested lies making it much faster and easier to use. Originally floppy disks were eight inches in diameter, and held 80 kilobytes, approximately one notepad document. By the time computers were arriving in every home the disks reduced to five and eventually the three and a half which is still used today mainly for troubleshooting purposes since most programs have grown beyond their capacity of 1.44 megabytes.

The same concept is used on the CD-ROM drives and hard drives of today. CD-ROM's are an optical drive meaning that the information is read off a different type of surface using the changes in the reflection of a beam of light. This process allows for an exponentially larger amount of information to be stored on a disk of similar size. However, the process of placing information on that surface is a much more involved and unless a special disk is used that information is permanent. The manner in which this information is stored and read has evolved into the DVD, dual-layer DVD, Blue-Ray, and HD-DVD, which have increased storage capacities due to storage tactics and different color lights. The size of the programs being used is the main distinguishing factor in which type of disc to use. When programs being used require multiple disks to accommodate them then consider the next version because soon programs will require stacks of them and eventually will not be available.

Hard drives are a fixed stack of disks, called platters, with individual reader arms between them. In a hard drive the magnetic disks are made of special materials with special coatings to increase the amount of information that can be stored on them, and spin much faster than a CD or DVD. Hard drives are used as the main storage point for all the computer's programs. The capacities of these drives are increasing constantly, capable of storing as much as 1500 CD's and are an integral part of any modern system. A computer has firmware built into the mother board that will allow it to function without a hard drive, but there are only the most basic actions available.

Random Access Memory

RAM is the bridge between the computers storage and processing speeds. RAM is a temporary place to store information between all the storage devices and the processor. A complete program is huge and only certain instructions from those programs are regularly used. Those most common files are kept temporarily in the RAM for quicker reference. Many

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