The difference between a windowing system and a window manager

This is what I have been able to gather so far:

Applications communicate over some sort of private API to the WindowServer process, the WindowServer process is the one that actually gets hardware events (mouse, keyboard) and dispatches those to the client applications. (this is still an open question: what protocol do they use if any, do they use Mach ports and MIG, or some Socket-based API, not sure).

Some information is here:

https://developer.apple.com/mac/library/documentation/MacOSX/Conceptual/OSX_Technology_Overview/GraphicsTechnologies/GraphicsTechnologies.html#//apple_ref/doc/uid/TP40001067-CH273-SW1

The WindowServer is the Quartz Compositor. Typically applications use the Quartz2D API which exposed in the CoreGraphics API (CGXXX funtions). Applications create CoreGraphics "Contexts" (CGContext) and draw there. Whether the context is pushed when it is done as big bitmap, or if the operations are sent to the server like they are on X11 is still an open question.

There is a limited API exposed to control certain aspects of the WindowServer process, the sort of configuration settings that are typically done from the Settings application, but there is no documentation on how apps actually communicate graphic requests or pump messages from the server, other than the Carbon/Cocoa APIs exposed.

A terminal emulator provides a standardised character based interface for text mode applications, it emulates the behavior of real or idealised hardware.

Consoles typically run some sort of terminal emulation, (linux console emulates a VT220 with some additions)

A terminal was dedicated hardware that implements the standard and iwas connected to ther server via a serial connection either directly or via a concentrator. The term is often used to include terminal emulators, it can also include GUI terminals that use X or RDP instead of being text based.

A terminal multiplexer emulates several terminals and mixes their output and directs input in a way that is useful to the user.

Xterm is a terminal emulator the runs under a GUI (X). a window manager can be used to resize and relocate the terminal windows that xterm uses. xterm also has a graphical capability where it emulates a graphical terminal, but there aren't many applications that can exploit this, i know of only two gnuplot and dosemu) most other GUI based terminal emulators dsiplay text only.