Defragment – it is a process used to decrease the amount of fragments produced in a storage medium such as a hard drive. This process is complete once the files on the storage device are re-organized and the least number of fragments is reached. More free space results in the disk once this is followed by” compacting” the disk drive in order to inhibit the formation of more fragments. As we mount up data on storage drives, they become loaded with non-contiguous blocks. One file gets scattered across the whole drive and performance of the system becomes weak. This is the point where defragmentation helps. Storage media should undergo this process as soon as fragmentation level reaches 10%.