Scott Charney, Corporate Vice President of Trustworthy Computing, told the RSA security conference how Device Guard will give organizations the ability to lock down devices in a way that provides advanced malware protection against new and unknown malware variants.

It is basically provides better security against malware and zero days for Windows 10 by blocking anything other than trusted apps signed by specific software vendors.

When an app is executed, Windows decides if the app is trustworthy, and notifies the user if it is not.

Device Guard can use hardware technology and virtualisation to isolate that decision making function from the rest of Windows, which should stop malware that gained a full system privilege.

Device Guard will frequently be used in combination with traditional AV and app control technologies which will use Device Guard to help block executable and script based malware. Meanwhile AV will continue to cover areas that Device Guard doesn't