What is the meaning of: Xorg, display manager, X server ?

I don't really have a problem, I was just wondering where I could find some documentation about what exactly X server, Xorg, LightDM and stuff like that does.. I always stumble upon those terms, I know they have something to do regarding the graphics, but I'd like to know more.

Solution 1:

X-Windows is a Unix/Linux Client-Server system. Although usually on the same computer, the Client and Server can be on different computers, unlike Microsoft Windows.

X11 is a network protocol. It encodes things such as graphic primitives, images, pointer motion, and key presses.

X clients are graphical applications like Firefox.

Xorg is an X server. It implements X11 and provides an interface to keyboards, mice, and video cards.

Gnome, KDE, LXDE, and Xfce are desktop environments. They provide libraries and specifications that applications use

When running X-Windows, instead of a console login, the Display Manager i.e. Lightdm starts up. The DM starts the X-server and asks for login credentials and then launches the user's desktop environment.

Hope that helps.

Solution 2:

For background information on applications running on Ubuntu I always find the following resources useful:

• Ask Ubuntu
• Ubuntu Wiki
• Ubuntu User Documentation / Community Wiki

For deeper insights or other views on applications that run in different distributions we can also find a lot here:

• Ubuntu Package Information often give a link to a project's home page
• GNOME Wiki for anything related to GNOME
• freedesktop.org Wiki
• Debian Wiki
• Arch Wiki
• Wikipedia with its basic informations and its links to relevant pages
• Google! No kidding, this is way fastest to find a project's page

This list is incomplete, I know.