Galaxies are massive collections of stars, gas, dust, and dark matter. They are both the birthplace of stars and planets and the signposts of the universe. By studying what happens inside galaxies, we are able to understand the conditions under which stars form. By studying the galaxies themselves, we can understand how the environment shapes their structure and makeup. By studying the distribution of galaxies, we gain insight into the structure and evolution of the universe as a whole. In this class, we will undertake a detailed, quantitative study of galaxies, with particular attention to the environment in which galaxies form and evolve and their place in the universe as a whole.