My two cents
Continuous adding, removing and editing cause files to get divided into fragments and get scattered across the HD. Defragmenting is the process where scattered file clusters are consolidated into a contiguous arrangement thus making the task of accessing them easier and faster. This happens because the file data gets arranged in clusters that lie sequentially rather than in a non-contiguous fashion helping the natural way the hard discs read data. The optimal speed of the HD will in turn help its other performance partners such as the CPU/RAM/MOBO/video card work faster as well. Faster file access time for your HD would mean a better speed of actions such as loading of your Operating System, file transfers particularly for large files, searching of files, file saving and reading in general.Its good to defrag whenever a lot of files are added/deleted or once in a week, although sometimes, systems warrant daily defrag.
Okay I've been noticing that whenever I defrag my com, it seems like there is a lot more fragmented files each time. What exactly is a fragmented file. If it's bad what do I do about it?
You should run a disk cleanup, chkdsk and then defrag (if ur using the XP defragger, best done is safe mode)cos if some program interrupts while the defragger is running, files will not be defragmented. If ur doing it for the first time, it may take long. Or you can use third party tools that are faster and have advanced features. Here's a nice utility which is free.http://www.majorgeeks.com/download.php?det=1207