Over time, your registry will become clogged up with needless information from programmes that have been uninstalled in the past. Unfortunately, Windows has never been very good and properly and installing programs for example. Details are always left over in the registry and sometimes in the program files folder itself. All of this data not only takes a hard disk space, but also slows down your computer. To really understand how to clear your computer from any registry issues and learn how to make your PC run at speeds up to 5 times what it is doing now, I suggest you click here: registry cleaner reviews