  These notes provide a brief introduction to the ABJM theory, the level k U(N)
x U(N) superconformal Chern-Simons matter theory which has been conjectured to
describe N coincident M2-branes. We discuss its dual formulation in terms of
M-theory on AdS_4 x S^7/Z_k and review some of the evidence in favor of the
conjecture. We end with a brief discussion of the important role played by the
monopole operators.
