  Thermal convection is one of the main mechanisms of heat transport and mixing
in stars in general and also in the photospheric layers which emit the
radiation that we observe with astronomical instruments. The present lecture
notes first introduce the role of convection in astrophysics and explain the
basic physics of convection. This is followed by an overview on the modelling
of convection. Challenges and pitfalls in numerical simulation based modelling
are discussed subsequently. Finally, a particular application for the
previously introduced concepts is described in more detail: the study of
convective overshooting into stably stratified layers around convection zones
in stars.
