  In this lectures I discuss the electronic liquid crystal (ELC) phases in
correlated electronic systems, what these phases are and in what context they
arise. I will go over the strongest experimental evidence for these phases in a
variety of systems: the two-dimensional electron gas in magnetic fields, the
bilayer material Sr$_3$Ru$_2$O$_7$ (also in magnetic fields), and a set of
phenomena in the cuprate superconductors (and more recently in the pnictide
materials) that can be most simply understood in terms of ELC phases. Finally
we will go over the theory of these phases, focusing on effective field theory
descriptions and some of the known mechanisms that may give rise to these
phases in specific models.
