Students will learn what it means to take the direct product of groups. They'll start by learning what it means to take the product of two groups, then three, then finitely many, then infinitely many. They should see examples involving both abelian and non-abelian groups.
TODO: Characterization of groups of order 4, as seen in the video by Michael Barrus. What are the basic properties of direct products, and can we prove them?