  These notes have been written to complete a mini-course "Introduction to
(generalized) Gibbs measures" given at the universities UFMG (Universidade
Federal de Minas Gerais, Belo Horizonte, Brasil) and UFRGS (Universidade
Federal do Rio Grande do Sul, Porto Alegre, Brasil) during the first semester
2007. The main goal of the lectures was to describe Gibbs and generalized Gibbs
measures on lattices at a rigorous mathematical level, as equilibirum states of
systems of a huge number of particles in interaction. In particular, our main
message is that although the historical approach based on potentials has been
rather successful from a physical point of view, one has to insist on (almost
sure) continuity properties of conditional probabilities to get a proper
mathematical framework.
