In this paper experiments on laser cooling, collimation and manipulation of a sodium atomic beam, such as the transverse collimation and decollimation of an atomic beam by a standing wave or a misaligned standing wave, longitudinal cooling of an atomic beam by a diffuse light field, sub-Doppler cooling in a blue detuned standing wave, are reported. The basic concept on atom optics is developed. An experiment on a method for the injection of atoms into an atomic cavity is also discussed.