The physical interactions of the macroscopic world can be described and predicted using the laws laid down by Newton. But this world consists of microscopic and submicroscpic particles. To fully comprehend the macro-world, scientists must be able to understand the physical principles which govern the micro-world. Here the laws and principles of Statistical Mechanics and Thermodynamics are of fundamental importance, and this new textbook provides a clear grounding into these important and fundamental areas. It is unique in treating thermodynamics as an application of probability theory, bring a fresher and more logical approach to a difficult subject area, Each chapter ends with problems, and review questions and solved exercises are also included, providing students with practical applications to test their knowledge in a complex subject. courses in thermodynamics in physics departments with a solid training in the fundamentals of statistical mechanics and thermodynamics. Numerous problems and supplementary exercises will help reinforce learning, and an accompanying PC disk provides programs for further learning.