GDM (GNOME Display Manager)

The GNOME Display Manager (GDM) is a program that manages graphical display servers and handles graphical user logins.

GDM3:- GDM3 is the default display manager for GNOME Desktop which manages the graphical display servers and user logins. GDM do not include any XDM code and was written from scratch.

Features of GDM3

• GDM3 has a much more efficient fast-user-switching support.
• GDM3 is also accessible to users with disabilities.
• GDM3 is Gnome’s default display manager and it’s compatible with X and Wayland.
• GDM3 allows users to customize or troubleshoot settings without having to resort to a command line.

Installing GDM3 in Ubuntu

GDM3 can be installed in ubuntu (Debian based system) using below command.

sudo apt install gdm3

LightDM:- LightDM is the default display manager for Ubuntu. It is faster, lightweight and highly configurable. It uses various front-ends to draw login interfaces (called Greeter).

Features of LightDM

• It is faster, lightweight and highly configurable.
• Its usage lower primary memory that results in faster performance.
• It is the default display manager for Ubuntu.
• A well-defined greeter API allowing multiple GUIs.
• Low code complexity

Installing LightDM in Ubuntu

LightDM can be installed in ubuntu (Debian based system) using below command.

sudo apt install lightdm

Similarity in gdm3 lightdm

• Both gdm3 and lightdm are login managers.
• They both provide graphical login capabilities as well as remote logins using the XDMCP protocol.

Conclusion

As the name suggests lightdm is more lightweight than gdm3 and it’s also faster. It is recommended to use lightdm. lightdm is ranked 2^nd and gdm3 is ranked 6^th in the best Linux Display Manager category.