No, Windows Defender is a free antivirus program developed by Microsoft for Windows 8 and later versions of the Windows operating system. It is available as part of the Windows operating system and does not require any additional purchase to obtain or use it.
Windows Defender scans for and removes viruses, spyware, and other malicious software from your computer. It also monitors and helps protect against threats originating from emails, websites, files, and networks.
The Windows Defender interface is simple, allowing users to easily enable or disable the program, schedule scans, and modify the level of virus and spyware protection they wish to have enabled.
When configured properly, Windows Defender offers thorough protection against potential threats. Whether it is necessary to run Windows Defender is another matter; many users have noted that Windows already includes several layers of security and that running multiple anti-malware programs can conflict with each other. Still, Windows Defender offers extra peace of mind, especially if your computer is connected to the internet or accessed by multiple people.
In addition to the free version of Windows Defender, Microsoft also offers a premium version called Microsoft Security Essentials (MSE). MSE provides the same basic protection as the free version but adds real-time scanning, automatic updating of virus definitions, and support for Windows 7, Vista and XP.
For most users, the free version of Windows Defender should provide adequate protection. It is updated regularly, runs silently in the background, and does not interfere with other applications on the computer. It is a good idea to periodically check Windows Update to ensure you are using the latest version of Windows Defender. If you need more comprehensive protection, MSE is an excellent choice.