Observations of rotation and velocity fields of cool stars

Adoption of the dynamo hypothesis leads to investigations of the driving forces: rotation, differential rotation, and convective velocities and their patterns. Attention must also be given to the effects of the dynamo: magnetic field strengths, starspots, the chromosphere and corona,flares and other eruptions, rotational braking, and the geometrical configuration of the fields insofar as they affect the granulation. In this review, emphasis is given to the observational information now available. The general measurements of nonthermal velocity fields referred to as turbulence are analyzed. Other photospheric topics are then discussed, among them stellar granulation, magnetic fields, oscillation, and stellar rotation. A selection of relevant chromospheric and coronal information is presented.