Clusters, ranging in size from many millions of atoms, constitute a fascinating field of research which cuts across boundaries of physics, chemistry and materials science. They are formed by most of the elements of the Periodic Table, and the types of bonding and the resultant clusters are equally as varied. This book serves as an introduction to atomic clusters - ranging from weakly bonded clusters of argon to strongly bonded carbon clusters and metal nano-particles. The author has written this book specifically for students on Master's courses, undertaking a module or short course in this field. The book is an introduction to the rapidly growing research area of cluster physics which underpins the increasingly important field of nanotechnology. It includes worked examples throughout which increase in difficulty to enable lecturers and students to gauge their understanding and progress. The book describes the experimental generation, detection and interrogation of clusters and theoretical approaches developed to aid understanding of their physical properties. Clusters are classfied according to their bonding types and examples are given of present and possible future applications of clusters in electronic, optical and magnetic devices.