The Windows Registry is often called the heart, brain, or soul of the Windows operating system. To some extent these experts are right. The Registry is necessary for Windows to function correctly.
A computer always crashes eventually if its Registry becomes damaged or corrupted.
The Windows Registry contains information on drivers, hardware settings, services, protocols, application data, and much more.
Many Windows experts suggest that all systems running Windows should have Registry maintenance performed every three months, if not more frequently. It is important to remove old references to items that have been removed from inventory. Any person that installs or uninstalls software often should fix the windows registry more frequently. Experts recommend so because installing and uninstalling software are two main reasons for unused or unwanted entries.
Be sure to take great care. If the Computer Registry is not repaired correctly the whole system could crash.

Registry is an important and vital role while Windows starts and is in use. If you try to %LINK3% yourself, changing, moving or deleting them damages any of the important Registry files, the result will be major problem. Multiple Registry tools possess built in backup resources for this very reason.
As a matter of fact, there is an editor built right in to the Windows Registry. Go to Start, Run, type regedit.exe, then click OK to view the built-in Registry Editor. This built-in editor allows you to easily navigate within the Registry so that you can make any changes necessary. The problem with this approach is that the typical Windows system has hundreds of thousands of Registry entries. Some are just hard to understand. You will find some to be really ambiguous while others are fraught with exceptional peril.
Regedit does not have any fail safe features that will prevent you from making harmful changes to the registry. Regedit can not know what is needed or not needed, or is no longer being used by the system. There is also no way to determine what is lacking. So in itself its not the best tool to use to fix the computer registry.
There are hundreds of resources provided to do this particular task, which means that it isn't necessary for you to become a complete expert on the hundreds of thousands of potential entries that you might encounter in Windows Registry. The majority of registry tools take care of this automatically.