Combustion is very much an interdisciplinary topic, drawing together elements of chemistry, fluid mechanics and heat transfer. It is an ingredient in many undergraduate degree programmes, ranging from a pivotal role in fuel science through to a component part of courses in chemical, process and building services engineering. For many students in those disciplines where combustion in heating plant is an important part of their studies, there are often problems in coming to grips with the basic principles underlying the combustion of hydrocarbon fuels. In particular, the concepts of chemical and related thermodynamic changes can prove difficult to assimilate. The scientific literature dealing with combustion tends to be rather polarised, with a wealth of literature aimed at the specialist reader, but at a basic level the fundamentals of this important process are often treated rather tersely in textbooks on thermodynamics. The objective of this book is to provide an introduction to the basic principles of the combustion of hydrocarbon fuels in heating plant for buildings and industrial processes. In those chapters where practice in problem solving can make a positive contribution to understanding, some numerical problems have been included. Acknowledging the ever-widening use of computers in technical education, a number of algorithms which can be easily coded up for solving numerical problems have been incorporated in the text. These can prove particularly useful in, for example, the calculation of certain fluid properties, either for use in hand calculation or for incorporation into larger programs.