Meaning – The term defragmentation, refers to the process of re-organizing the files on a hard disk in such. way that parts of each file are stored in contiguous sectors on the disk, resulting in the improvement of computer performance and also maximising the disk space.
Usually, when a file is saved on the computer, it is stored in dedicated sectors on the disk, but more often than not, they also reserve some buffer sectors which offer no real purpose, but it reflects in the available disk space.
Windows based PCs offer the users a GUI based button, which, on activation, initiates the process of defragmentation on the hard disk. The process takes a few seconds to few minutes, but at the end, you will see a marked change in the available hard disk space, as all the buffer sectors are released from use and made available as disk space.