This was a standard speedy revision session in group theory. Axioms, subgroups, cosets, normal subgroups, quotient groups, isomorphisms and homomorphisms.
It was nice to get back into something that was familiar to me.
Next chapter is vaguely named "Towards Classification". Seems to introduce the concept of a direct product, and revise orbits and stabilisers. I'm hoping I'll be able to get through this quickly, as I'm starting to fall behind slightly...