I mean system restoration in windows...

i mean system restoration in windows.....

Windows monitors changes to specific files and saves a copy of the files before the change is committed. The saved files can then be later restored using the System Restore interface. Additional technical info about the feature and the files that are monitored is available at the resources below. Since System Restore does not monitor every single file in the filesystem, it is important to realize that System Restore only augments but does not replace the need for full system backups to completely recover from a corrupted installation. Unfortunately, System Restore is often regarded as a complete "undo" for any computer ailment. Depending on what is wrong with the computer, performing a blind restore has the potential to corrupt the installation even further in some situations.

Resources:
Wikipedia: System Restore (http://en.wikipedia.org/wiki/System_Restore)
Microsoft Support: How to restore Windows XP to a previous state (http://support.microsoft.com/kb/306084)
Microsoft Developer Network: Windows System Restore (http://msdn.microsoft.com/en-us/library/ms811705.aspx)