Desktop Environments

A desktop environment is the graphical environment of a desktop computer.

A desktop environment usually consists of an experience. That is, each desktop environment comes with its own app and widget ecosystem.

Components: A panel, dash, file manager, e-mail client, settings, additional apps

The desktop environment's shell is the program that combines the window manager, compositor, panel, etc.
So if you swap out the compositor, the function of the others stay the same.

So in other words, a desktop environment consists of a shell and utilities.