The Registry Editor is a tool that lets you change settings in the Registry. If you are like me, you will like the Registry Editor so much that you will keep a shortcut to it on your desktop. (No, I'm not kidding.) If you are like other, not-so-masochistic people, you will take a look at it and shut it down fast.
In most cases, users can change system settings through Control Panel, without going into the Registry Editor. Actually, end users should never edit the Registry unless it is absolutely necessary. If you were to introduce an error into your Registry, the computer could become nonfunctional. It is true that the Registry can be restored, but let's face it—if you were to hose your whole system by playing with the Registry, would you want to go back in?
But if you are writing your own application and need to add settings to the Registry or make other Registry adjustments, Control Panel won't do the dirty work for you. Once you open the Registry Editor, you can use the menus to add keys and values. You can also import or export Registry data.