This study, originally two volumes, covers both the classical aspects of vibration and the quantum oscillator. Part I discusses both linear and nonlinear vibrations. Part II looks at quantum systems, concentrating on vibrations in atoms and molecules and their interaction with electromagnetic radiation. The similarities of classical and quantum methods are stressed.Pippard, A. B. is the author of 'Physics of Vibration ', published 2007 under ISBN 9780521033336 and ISBN 0521033330.