• A Mac defragmenter groups together related bits of data on your hard disc to speed up the loading of files and programmes. Disk defragmentation reorganises the files on your hard drive so that your computer can access them more easily. However, because Macs can defrag themselves, defragging is rarely necessary.
• Understanding how your computer saves data is crucial before using a Mac defrag. Any hard disc drive will fracture over time (HDD). The order in which data is stored has an effect on how quickly it can be written to or read from a hard drive.
• When you save a Windows PC file, for example, the data is written wherever there is space on your hard drive. If the file is too huge to fit in one location, it will be divided and saved in other locations. Your computer will maintain track of where everything is, but it will begin to slow down while it searches for all the necessary data to open a file or run a software.

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