Microsoft Defender is the simple way to protect your digital life and all of your devices. It's included as part of your Microsoft 365 work or school subscription at no extra cost.
Microsoft Defender is a security app that helps people and families stay safer online with malware protection, web protection, real-time security notifications, and security tips. Microsoft Defender is included in a Microsoft 365 Family or Personal subscription and works on your phone (Android or iOS), PC, and Mac.
Windows Security, formerly known as Windows Defender Security Center, is an app built into Windows 10 or 11 that helps keep your PC more secure. It includes Microsoft Defender Antivirus, an antivirus tool that helps protect you against viruses, ransomware, and other malware.
Windows Defender Firewall is firewall software built into Windows that controls which network traffic is allowed, or blocked, from passing to or from your computer across the network. Windows Defender Firewall is on by default.