Defragging your hard disk can help improve your PC’s speed and performance, but it is not necessarily necessary. Depending on how much you use your computer and the type of activities you do on it, you may notice a significant improvement in speed after defragging your hard disk. However, if your computer is already performing well, then you may not need to defragment it. If you are unsure if defragging is necessary, it is best to check with an IT expert for advice.