All processes that occur in a cell require energy that ultimately derives from the sun. The original processing of light energy by plants, the conversion of this energy into a useable form, its utilisation to do work, and its incorporation into storage molecules comprise the subject of this book. Michael Guppy is a retired Associate Professor of Biochemistry from the University of Western Australia. The book is based on a lecture series on metabolism that was developed over twenty years. It is unique in that energy processing is simplified and clarified by being distilled into a series of recurring concepts and themes. The different metabolic pathways are thus treated not as separate entities, but as interlocking parts of a whole that have a common purpose. This approach enables lessons learned from one pathway to be carried over to subsequent pathways, resulting in a decrease in the amount of new information that is encountered as the book proceeds.In the final chapter we are reminded that although biochemistry may be a strange world to many, it is very much a part of us all. The concepts and themes encountered in the book are applied to the issue of how we burn off energy (lipid stores), and what steps we can take to avoid the disabling and life-threatening affliction of obesity.