Microsoft's Iaan D’Souza-Wiltshire penned an announcement heralding the debut of Microsoft Defender for Mac. It's essentially the same app as Windows Defender on Windows 10. Microsoft Defender offers Mac users the same kind of protection that its Windows counterpart offers Windows users. For now, Microsoft Defender is only available as a limited preview. Microsoft last released a web browser that ran on Macs way back in 2003.
Source: Forbes March 21, 2019 15:56 UTC