The Windows registry is a very complex database of different software and hardware preference and settings files.  The registry allows your software and settings to remain the same after you have turned off your computer.  The problem with Windows, however, is that it allows programs to write to the registry and then leave these entries behind indefinitely.  If you’re looking for the best registry cleaner then I definitely suggest checking out a program called RegCure.  RegCure is a very easy to use software program that lets you easily and quickly clean up the registry of all the excess entries that sometimes build up over time.