Q:

what is desktop environment and where is placed in linux architecture

What is the role of the desktop environment in the architecture of a Linux-based operating system like Ubuntu?
Can anyone explain what a desktop environment is and how it relates to other components of the system?

A:

In nutshell,

The Linux Kernel runs on the hardware. (init and other essential processes
start)
After essential processes are up and running, Kernel runs X-server
(another set of software).
Desktop environment such as Gnome, KDE, DWM runs using the
facilities provided by the X.

Everything works in layered fashion.

