Hard drives are memory storage devices for computers that you use to access, retrieve, and store data. A hard drive functions by writing information onto, or reading data off of, a hard disk. The benefit of a hard disk is that it can hold lots of information, as opposed to its smaller, portable counterpart, the floppy disk. Hard disks can have a maximum storage capacity of anywhere from a few megabytes of data to tens of gigabytes, while floppy disks can only hold about 1.4 megabytes of information. The disadvantage to hard disks is that they are generally fixed and immoveable, in contrast to the floppy, but removable hard disks are available. In terms of speed, the hard disk drive locates and pulls up data in a few milliseconds, or millionths of a second, which is much faster than a floppy disk. Hard disk drives sometimes utilize a technique called caching to accelerate the seeking or accessing process. The term caching means that when the hard disk drive is asked to recall a particular piece of information, it first checks the memory buffer to see if the information is already stored there. By doing so, the hard drive can speed up the process of applications, since the desired piece of data might already be there. The computer simply can serve the cached information, instead of resorting to the more time-consuming process of seeking and transferring data from the hard disk. Even if the data is not cached, however, the access speed of a hard drive still exceeds that of a floppy disk or compact disk.
c2004 Bluestreak Media. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.