Chambert-Loir and Ducros have recently introduced real differential forms and
currents on Berkovich spaces. In these notes, we survey this new theory and we
will compare it with tropical algebraic geometry.Comment: 25 pages, notes for my survey talk given at the Simons Symposium in
St. John from 1.4-5.4.2013. In the second version, a sign error in the
definition of the integral is corrected and the exposition in section 7 is
slightly change