Abstract
The author discusses the physics of B mesons which were first observed directly in 1986 through their full reconstruction. Emphasis is put on the experimental results on exclusive and inclusive B decays obtained since then by the e+e- experiments ARGUS at DESY and CLEO at Cornell. The results are discussed in the framework of the standard model with three families, on which in particular the B0B0 mixing observed in 1987 by ARGUS puts strong constraints.