Think of a hard drive as a long sheet of paper when you first install your operating system and put things on it everything is stored in basically a straight line starting at the top and working your way down. As data is added and deleted, the free space on the hard drive will get smaller and will tend to spread out in different locations on the hard drive instead of in one general location. It means that when you want to run one of the programs, the computer will run quicker because the hard drive doesn’t have to do extra work by fetching data from different areas of the hard drive. It also puts all the free space on the hard drive together, and after the defragmentation is complete, the files on your hard drive where all the related files are together and everything is beautiful and organized. It puts all the files that belong to a specific program together, all the files that belong to a specific video together, the same with document music, and so on. So, when you do a defrag the computer, it will reassemble all of the related chunks of data that had been broken up, and it’ll put them together in the same physical location. That data is divided into multiple chunks of data stored on the hard drive, so after a while, your hard drive data is spread out in mixed in with other data files. It reorganizes related data files and puts them in the same physical location on your hard drive. For example, you installed data on your hard drive, such as programs, documents, music, video, etc. Defragmentation reduces the number of fragmented files on a hard drive. The reason that disk defragmentation is a thing is because of the process following which a mechanical hard drives stores data. It boosts the performance and increase the loading speed for your files and folders that had degraded.