“Expository” means “intended to explain or describe something.” An expository essay provides a clear, focused explanation of a particular topic, process, or set of ideas. It doesn’t set out to prove a point, just to give a balanced view of its subject matter.
Expository essays are used to explain something in a neutral way. Writers use expository essays to demonstrate their knowledge or expertise in a certain area. Teachers often assign expository essays to test their students’ understanding of a topic.