Wayland is a piece of the linux desktop software stack. If you're on a Mac or Windows, it won't mean anything to you. Linux historically has used X11 for drawing the desktop. Wayland is a replacement for X11. It's big news because it's been a long time coming, and fixes a lot of longstanding issues. Unfortunately it also creates some new issues (screen sharing, hot key apps, etc), but they're being actively worked on and are very close to being completely solved.