Microsoft SmartScreen is out there on the perimeter helping you stay safe while you’re online and Windows Defender is a robust back stop that will help defend you from advanced malware. Windows Defender is a robust antimalware solution that is included as part of Windows 10, working right out-of-the box to help you stay protected. Windows Defender provides the defense you need; it is constantly updated to meet evolving threats as they are identified and is quick to detect and protect you against emerging malware, seen in the first critical hours. Windows Defender uses a highly scalable and geo-distributed backend service in the cloud that leverages data from about one billion devices to draw lightning fast insights and respond in hundreds of milliseconds.