However, I still field plenty of questions from lots of people about this, and a lot of the time, it's extremely simple stuff: "What is X?" "How does it interact with my graphics card and mouse/keyboard?" "What do apps use X for?" "What is Wayland, and how does it fit into the picture?" "What problems did X have that made us want to write new display server technologies?"
These sort of questions were what inspired me to write "The Linux Graphics Stack" in the first place, but there's really never been a comprehensive, historical writeup of our display server technologies in general. So, I chose to spend my free time at Red Hat writing it.
A very fun look at what X actually is - including embedded X server sessions running in your browser using HTML5 canvas. Fancy.