Delta Scuti and related stars

Abstract

An extensive review is given of the current status of our knowledge of the stars in the lower instability strip. Current problems are emphasized. Particular attention is given to the following areas: the confusion concerning naming and the implied astrophysical properties (often erroneous), single and multiple periods, the effect of rotation and metallicism on pulsation, the nature of the so-called dwarf cepheids, and pulsation in Ap stars. Various reports of unusal and strange effects are also discussed with personal, possibly biased judgment on their reality.