  In these lectures I will review the approach to glasses based on the replica
formalism. Many of the physical ideas are very similar to those of older
approaches. The replica approach has the advantage of describing in an unified
setting both the behaviour near the dynamic transition (mode coupling
transition) and near the equilibrium transition (Kauzman transition) that is
present in fragile glasses. The replica method may be used to solve simple mean
field models, providing explicit examples of systems that may be studied
analytically in great details and behave similarly to the experiments. Finally,
using the replica formalism, it is possible to do analytic explicit
computations of the properties of realistic models of glasses and the results
are in reasonable agreement with numerical simulations.
