Hard drives have more moving parts than most of your computer.

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A computer has very few moving parts to wear down, break down or slow down. The obvious exception is the hard drive. It has many moving parts that must operate at near perfection to fetch and store data efficiently. This fact makes the hard drive the prime suspect when processes seem to be lagging. If the hard drive takes too long to provide the data a program needs, processing speed can quickly change from instant to "hurry up and wait" status.

So what do you do about it? Disk defragmentation has long been the go-to cure for a sluggish computer. Until recently, if you asked most computer geeks how to speed things up, they would tell you to try a "defrag" before just about anything else. Today's faster, larger and more efficient hard drives make defragmentation a less effective solution for slow computers. In most cases, however, a defrag remains a relatively simple way to boost your system's speed and efficiency.

­In this article, we'll explore the defragmentation process to learn what it is, how it works and the potential benefits. We'll also explore advances in hard drive and operating system technologies and how they affect the defragmentation process.