A standard text combining statistical physics with thermal phenomena, this book presents a unified approach to provide a deeper insight into the subject and to bring out the subtle unity of statistical mechanics and thermodynamics. Suitable as a text for undergraduate courses in physics. KEY FEATURES ? Presents a new pedagogical approach introducing macroscopic (classical) thermodynamics through the statistical mechanics. This new approach is increasingly sought to be introduced worldwide. ? Magnitudes of physical quantities under discussion are emphasized through worked-out examples. ? Questions and exercises are interspersed with the text to help students consolidate the learning. ? Techniques developed in this course are applied to actual modern situations. ? Many topics are introduced through the problems to help inculcate self-study.