The windows registry is both of those things. It has a "hive" which is part of the user profile. User preferences are stored there ("HKEY_CURRENT_USER"). Sys

The windows registry is both of those things. It has a "hive" which is part of the user profile. User preferences are stored there ("HKEY_CURRENT_USER"). System-wide preferences are stored in a "hive" for system apps ("HKEY_LOCAL_MACHINE"). It allows applications to mix and match system-wide stuff with user-specific stuff, which only differs by which "hive" it wants to query against. It has several data types for different types of records. There's conventions for how to store things (although apps can do whatever they want), so apps usually store their state and config data under HKLM\SOFTWARE\MyCompany\MyApp for system-wide stuff, and user specific stuff will live under HKCR\SOFTWARE\MyCompany\MyApp. All in all, my experience has been that on average its usage is a bit more standardized than config files. Of course on windows, apps (particularly C# apps) ship both with config files and a boatload of registry entries. Lastly - by design, HKCR (the user profile hive) is assumed to sometimes have orphaned data. If a program is installed per-user, and you uninstall it as a different admin user than who installed it, the other user profiles cannot be loaded and modified by the installers thereby orphaning any other user data.