 So the bake node is a new node in Blender 4.1 which allows you to just store the evaluation of a geometry nodes setup on disk so you don't have to re-evaluate it again. For example, when you have some complex setup that takes a long time to calculate but you don't need to actually keep evaluating it over and over because it's not changing. You can just pop a bake node in there, press a button then work on the rest of the node tree without having to re-evaluate that all the time. This is gonna be in Blender 4.1 in the upcoming release. It's been a long time coming. We had simulation nodes in there for a while and those also do baking but now we can do it completely separated from simulations just as its own little feature and that's gonna be super useful.