With the latest Windows Insider build of Windows 10, Microsoft has killed off "Windows HomeGroup." Originally a part of Windows 7 in 2009 and continuing until now, HomeGroup was a way to share files and devices between computers on your network. This change will go live in the Spring 2018 update to Windows 10

Really does not phase me at all, except I'm happy to have less bloat on my machines. The handful of times I've tried to use HomeGroup it simply failed miserably compared to just sharing over the network without it. Quote below is from Microsoft's Blog post on Insider Build 17063.