An energy shortage at any point causes acute problems, whether domestic, public, regional or national. Without such things as oil, gas, electricity or coal, industry and transport would grind to a halt, and houses and offices would quickly become distinctly uncomfortable, if not uninhabitable. We are all agreed that energy is indispensable to our everyday requirements. But what is energy? We vaguely know about energy being synonymous with heat and work. We also know something about it as the driving force of animals and human beings and how it can be extensively tapped from nature. This book sets out to describe the precise meaning of energy, and how humans have brought about almost unlimited supplies of energy under their command, even to the point where they can produce the forces for unparalleled destruction. The world itself goes round because of kinetic energy, we move about because of chemical energy, and we use numerous forms of energy to do our work for us and to heat and move things. In telling us about the nature of energy, its various forms and how we can harness and utilise it, the author goes on to examine the question of energy reserves in the world and exploitation of new energy sources. Some fuels such as wood are already in short supply and others like oil and coal are fast becoming so., but the prospect for the future seems reasonably assured with the development of tidal energy, geothermal energy and nuclear energy - currently by fission of the atom, but one day by fusion as occurs in the hydrogen bomb. Clearly and accessibly, this book deals with a subject of vital importance to us all.