Microsoft Defender / Windows Defender

When we do updates and the security ones come in, they come in under two headings, Microsoft Defender or Windows Defender,
Anyone know what the difference is or why they do this ??

Microsoft Defender Antivirus is built into Windows 11. The Windows Defender is an app downloaded from the MS store, (I believe under the name Microsoft Defender Preview)This video shows you the difference.

Thanks glasskuter, it doesn't really explain, he gabbles and jumps all over the place and doesnt really explain except
to say one is anti virus and one just a display.
Also, I haven't downloaded anything from the store but still get updates to both.