The discovery of exoplanets is one of the greatest revolutions in modern astrophysics. Twenty years ago, we had no idea whether any of the countless stars out there beyond our solar system had planets or not. Today, things are totally different. Over one thousand planetary systems have been discovered. The universe is teeming with planets. And what strange planets they are - hot Jupiter-like planets skimming the surfaces of their stars, cold and lonely free-floating planets far from any star, planets made of diamond, planets with rain made of glass, super-Earths and even planets orbiting neutron stars. In this course we’ll bring you up-to-date with the latest research on exoplanets, and how it has revolutionised our understanding of the formation of solar systems like our own. This course is designed for people who would like to get a deeper understanding of these mysteries than that offered by popular science articles and shows. You will need reasonable high-school level Maths and Physics to get the most out of this course. This is the second of four ANUx courses which together make up The Australian National University's first year astrophysics program. It follows on from the introductory course on the Greatest Unsolved Mysteries of the Universe. It is not necessary to have done the introductory course first: all necessary background material is repeated here. It will be followed by courses on the violent universe and on cosmology.