With user impersonations you can easily impersonate any user on your site. This will come in handy when you need to debug an issue that a specific user is experiencing.
Impersonating a user will allow you to login to your application acting as a specific user.
To impersonate a user you can visit your users section in your application at /admin/users/impersonate.
Then enter the user email you want to Impersonate.
You will now have this screen, when done. You can Stop Impersonate the user.