  Solar-like oscillations are excited stochastically by convection. They occur
in stars with an outer convection zone, which includes the Sun and other stars
on the lower main sequence, as well as cool subgiants and red giants. This
chapter reviews the basic properties of solar-like oscillations and summarises
some of the main observational results. Mixed modes in subgiants and red giants
are discussed in some detail, including an introduction to the so-called p-g
diagram for avoided crossings.
