Defragment

[Couch Potatoe]

Defragmenting your hard disk is a great way to boost the performance of your computer. Though the term defragment sounds a little abrasive, it is actually a simple and helpful process. After all, a defragmented hard disk is a happy hard disk.
Adding and deleting files from your hard disk is a common task. Unfortunately, this process is not always done very efficiently. For example, when you delete a bunch of little files and add a new large file, the file may get broken up into mulitple sections on the hard disk. The computer will still read the newly added file as a single valid file, but the drive will have to scan multiple parts of the disk to read it. Because hard disk seek time is one of the most significant bottlenecks in a computers performance, this can drag down your computers speed quite a bit. If you have a ton of fragmented files on your hard disk, you might hear extra grinding, sputtering, and other weird noises coming from your computer.
You computer does not like having fragmented files any more than you do. This is why defragmenting your hard disk is such a good idea. When you start to hear extra grinding sounds, or your computer doesnt open files as quickly as it did before, its time to defragment. With Windows, you can use the pre-installed Intel defragment program to defragment your hard disk. You can also use a commercial software program like Norton Utilities to defragment your hard disk more efficiently and with more options. For Mac users, a disk utility such as DiskWarrior or Tech Tool Pro is the only way to do it. If you use your computer daily, defragmenting your hard drive once a month should keep the fragment-fiends away.

[Vania]

to make a computer organize its files and free space so that it can operate more quickly:

[exinilu]

(of software) reduce the fragmentation of (a file) by concatenating parts stored in separate locations on a disk.