Incubator is a 1-slot storage. Keeping any Farm Beast egg (like Fluffalo Egg) inside it will cause the egg to hatch significantly faster.
If you place a stack of eggs into the Incubator, they will be incubated one after another (one at a time).
It's possible to incubate an edible Egg that was produced by a Hen. It doesn't spoil when inside the Incubator, but there is a 50% chance that it will fail to hatch (no chicken appears, 1 Rotten Food is dropped onto the ground).
Husbandry (Agriculture tree).