This is a comprehensive guide to the often confusing subject of thermodynamics, for engineers, physicists, and chemists. The succinct entries are arranged alphabetically, allowing the reader to browse through the subject and to pursue a particular point, skipping or ignoring extraneous points. After twenty years of teaching thermodynamics, Professor Perrot knows exactly which areas students find difficult and has taken particular trouble with these points. The entries explain the words and phrases that crop up in thermodynamics without recourse to pages of mathematics and algebra: the main aim being to explain and clarify the jargon and concepts. Professor Perrot achieves this aim while maintaining a refreshing lightness of prose style, in which spirit he also includes some asides on interesting people and events in the history of thermodynamics.