On Windows 10, every user account gets a unique identifier, known as the “advertising ID,” that tracks and collects their activities, which then advertisers and developers can use to show targeted ads in apps.

from https://www.windowscentral.com/how-stop-targeted-ads-windows-10-apps
https://www.windowscentral.com/sites/wpcentral.com/files/styles/large/public/field/image/2018/11/disable-advertising-id-windows-10.jpg?itok=GN-Y5GL9