Formerly known as Windows Defender, Microsoft Defender is an antivirus protection program that's included with Windows 10.

In fact, Windows 8 updates are the only way the built-in Windows Defender software that act as your device’s first line of defense gets virus definition upgrades.

If you turn on notifications for Windows Defender in Windows Security, it will keep you informed about your PC's health & the activities it is conducting.

As Microsoft makes another push to get users off of Windows XP, the company says that it will begin turning on Windows Defender to protect PCs that are left unprotected.