Microsoft Defender Antivirus (formerly Windows Defender) is an anti-malware component of Microsoft Windows. It was first released as a downloadable free anti-spyware program for Windows XP and was shipped with Windows Vista and Windows 7. It has evolved into a full antivirus program, replacing Microsoft Security Essentials in Windows 8 or later versions. In March 2019, Microsoft announced Microsoft Defender ATP for Mac for business customers to protect their Mac devices from attacks on a corporate network, and a year later, to expand protection for mobile devices, it announced Microsoft Defender ATP for Android and iOS devices, which incorporates Microsoft SmartScreen, a firewall, and malware scanning. The mobile version of Microsoft Defender also includes a feature to block access to corporate data if it detects a malicious app is installed. Microsoft Defender brand As of 2021, Microsoft Defender Antivirus is part of the much larger Microsoft Defender brand, which includes several other software and service offerings, including: Microsoft 365 Defender Microsoft Defender for Cloud Microsoft Defender Endpoint Microsoft Defender for Office 365 Microsoft Defender for Identity Microsoft Defender for Cloud Apps Microsoft Defender Vulnerability Management Microsoft Defender for Threat Intelligence Features Before Windows 8, Windows Defender only protected users against spyware. It includes a number of real-time security agents that monitor several common areas of Windows for changes which might have been caused by spyware. It also has the ability to remove installed ActiveX software. Windows Defender featured an integrated support for Microsoft SpyNet that allows users to report to Microsoft what they consider to be spyware, and what applications and device drivers they allow to be installed on their systems. Protection against viruses was subsequently added in Windows 8; which resembles Microsoft Security Essentials (MSE). It also uses the same anti-malware engine and virus definitions from MSE. In Windows 10, Windows Defender settings are controlled in the Windows Defender Security Center. In the Windows 10 Anniversary Update, a new logo is introduced and a pop-up notification will appear to announce the results of a scan, even if no viruses are found. Real-time protection In the Windows Defender options, the user can configure real-time protection options. Windows 10's Anniversary Update introduced Limited Periodic Scanning, which optionally allows Windows Defender to scan a system periodically if another antivirus app is installed. It also introduced Block at First Sight, which uses machine learning to predict whether a file is malicious. Browser integration