Microsoft's latest Windows 10 build, Build 17063 or Redstone 4, is going to Fast Ring previewers and includes the promised Timeline feature. This allows you stop a task on one WIndows 10 device and then pick up from where you left off on another, much like macOS's Continuity.
As well as letting you move from one device to another and keep working, Timeline provides a visual history of what you've been doing. This will allow users to look back through what they were working on rather than needing to remember the name of a file they were editing or what application they were using. It let's them answer questions like "Where's that document I was working on yesterday morning?" rather than having to remember the name of a file.
A User Activity is a single destination within your app such as a TV show, document or campaign in a game. The activity is recorded during an Activity Session with the system creating a history record indicating the start and end time for that activity.
This may sound like a relatively minor feature but, given my experience of using Continuity on a Mac, it's a very useful feature and one that will be of significant benefit.
Microsoft has provided some further information on Timeline in a blog entry including how it can be integrated by software developers.