How Does a Disk Defragmenter Work?

The Basics

A disk defragmenter is a computer utility designed to speed up an operating system by rearranging files in such a manner that it increases your computer's ability to access them. A disk defragmenter also has the ability to speed up the amount of time it takes for an operating system (Windows XP, for example) to load, as well as increase the rate at which files can be transferred from one location to another.

Fragmentation Causes

Fragmentation of a hard drive can be caused by a variety of things. The main cause is when an operating system splits up a file and stores it in different places due to a lack of space on the hard drive as opposed to simply storing the file all in one location. This means your computer has to look in multiple places to access a file as opposed to one. Storing larger files and a large number of files can add to the amount of stress and fragmentation a hard drive is experiencing.

Files that Cannot Be Moved

Certain files cannot be moved and can ultimately counter the effects of defragmenting a hard drive. Certain system files need to be stored in a specific place in a specific way, for example, and will prevent a hard drive from ever truly being 100 percent defragmented. There are ways to get around this (by moving them when the operating system is not in use), but it is often much more difficult a task than the average user can handle. It would produce results an average user would barely notice, if at all.