In Windows 8, Microsoft has greatly improved the operating system's ability to detect malware before it has a chance to run, experts say. Windows 8 should also make it more difficult for people to unknowingly install malware in the first place.
The latest version of the OS, officially launched Thursday in a splashy event in New York, includes two key features to detect malware that tries to run while Windows is booting up. Hackers typically like to get their software running before the OS is fully loaded in order to remain hidden from antivirus applications.
Source
A Guy