Windows Defender is part of Windows 10 and 11. If you are using any previous Windows software such as 7 or 8.1 don't. Windows Defender, which as I say is part of Win 10 and 11, is as good as any other freeby and is anti virus and anti malware. That's all I use and it's kept me virus and malware free for years. If you want anti virus software for a business machine don't even think about the free ones.