New users on a Mac have a certain set of default settings which are copied into their user profiles the first time they log in. Starting with Mac OS X 10.0.0, these settings have been stored in the following location:
/System/Library/User Template
Inside the User Template directory are a number of language-specific directories where the default settings for various languages are stored. This allows the new user’s default settings to be appropriate for their language and keyboard configuration.
As of macOS Catalina 10.15.0, the location of the User Template directory has changed to the following:
/Library/User Template
The reason for the change is that the /System directory is now stored in Catalina’s read-only volume for the OS. By moving it to /Library, the User Template directory and its enclosed language-specific directories remain readable and writable for those folks who prefer to deploy settings by making changes to the user template directories.