Description
Presents the graphical login screen where users choose an account, enter a password, and start an X11 or Wayland desktop session. It is part of the system startup path, not a normal app used after login.
Changing display-manager settings can affect whether users can sign in, which session starts, and how the login screen behaves. Administrators should keep a recovery path, such as a TTY login, before replacing or reconfiguring it.