For higher division courses in thermodynamics or statistical mechanics, Kittel and Kroemer offer a modern approach to thermal physics that is based on the idea that all physical systems can be described in terms of their discrete quantum states, rather than resorting to to the classic nineteenth century. Mechanics concepts. This book gives an elementary account of thermal physics. The theme is simple, the methods are powerful and the results have wide applications. Probably no other physical theory is used more widely in science and engineering.