X Display Manager

lastmod 2026-11-10created 2020-09-054 edits

An X Display Manager (XDM) is a program in the X Window System that shows a login screen, authenticates the user, and then starts a session. It launches and manages the local X server, and also accepts connection requests from remote X terminals via the XDMCP protocol. Besides the original xdm, there are implementations such as GNOME's gdm, KDE's sddm, and the lightweight lightdm.

See also

• xorg
• XDMCP
• xephyr
• gdm