cleanup.exe is a component of an internet cleanup application. It is used to remove files that are created while surfing including cookies, history, and more. This software works together with the common browsers and can be removed to free up system resources.
Non-system processes like cleanup.exe originate from software you installed on your system. Since most applications store data in your system's registry, it is likely that your registry has suffered fragmentation and accumulated invalid entries which can affect your PC's performance. It is recommended that you check your registry to identify slowdown issues