Defragmenting, or defragging, your hard drive on a regular basis will increase the overall health and speed of your computer system.
Fragmentation happens when your computer saves information in small bits across the hard drive that are not necessarily together or close to each other. When it recalls this data, it must search several places, taking up time and energy; it also causes slowdowns in program and operating system functions.
Programs run faster and more efficiently when the data is grouped together for easier access.
Extended Hard Drive Life
The mechanical parts of the drive have to travel less distance when the data is all in one place, thereby reducing wear and tear on the drive itself.
More Efficient Security
When an anti-virus program scans your hard drive, it takes less time when your drive is less fragmented.
The process of defragmentation can often point out and avoid bad sectors that could potentially cause damage if your data was saved in this area.