X11, or the X Window System, lets your graphical desktop environment display and control windows. Wayland is a replacement for X11. It’s designed to be faster and more secure. Here’s what you need to know about them.
The compositor works way more precisely. The tearing is gone, font rendering and high resoltution images are way better displayed. Multi monitor setups are better, including different scales for different monitors.
I think there are more, but these are the improvements on wayland only I recognised during the last half a year.
Unfortunately in production use Wayland feels like X.org from around 2000 (before the renaming). I was told not to worry about 'corner cases' but when small bugs pop up daily I just can't drive Wayland on my main office machine, although I'd really like to.
My trouble is the Wayland Desktop session in Ubuntu LTS or openSuSE-Leap silently failing ever so often on different machines after a Wayland update. On production machines that's not something I can tolerate nor have the time to investigate, with my employees waiting.
I've been using Wayland almost exclusively for around 2 years now and have had a way more stable and enjoyable experience than with X. Especially mixed refresh rate, VRR and scaling work way better, and the added security gives me peace of mind that sketchy / insecure apps aren't spying on me.