Windows operating system has implemented the System Restore option in its latest OS products with this in mind. It works up to a certain extent. Does not "recover" all files or data. There are some things and settings that cannot be recovered. Not to mention the time consumption that it takes the whole process to complete. There are methods that create an image of the hard disk, modifying the BIOS, assigning hidden extra portion of the HDD to keep a copy of the itself, or burning a media CD with an image of it. So if there is a problem with the operating system , and gets attacked by viruses, spyware etc or suffers from any misconfiguration, simply load the previous saved "image" stored in the HDD and the problem is solved. With time, this solution proved to be unreliable. Not only made unnecessary use of extra HDD space, but also carries the danger that if the stored image gets corrupted the whole protection system fails, and the only way to get a PC back to life is re-formatting the disk and installing the OS and programs again. Other methods make use of a Vitual machine, where none of the changes are made directly to the hard disk. Instead it happens in a virtual memory . The back draw of this method, is that it makes use of the system's resources to perform its functions. Some in more or less quantity but they are used for sure. It relies on the OS to work. You better have a good computer with lots of free HDD space and great amounts of "brain" if you decide to use this method with minimum complications. But technology never stops. And there are always new and better approaches to fix problems and to make our life easier, and the recovery solutions are not the exception. There are two specific products. One designed for Pcs and another one for Laptops. These products offer real time protection to the Hard disk, without using system resources, or making images of the HDD content. Their double kernel capabilities provide protection not only to the OS but to the CMOS. Why this products are much more effective? They work independently from the OS! Because they work at the BIOS level.