This is an excellent introduction to its subject, and one that covers far more ground than the modest title suggests. I'm not a scientist, but I found Philip Ball's writing admirably clear throughout, his text liberally supplemented by illuminating diagrams and photos. Pondering to begin with the nature of matter, the author leads you through basic atomic structure, via the fascinating history of synthetic molecule-making during the development of the chemical dyestuffs industry, to an absorbing account of the functioning of the molecules inside us - in DNA, proteins and so on. This leads naturally on to an explanation of how molecules are key to the structures of living organisms, even down to the `scaffolding' that helps DNA divide within cells along the intricate threads of the mitotic spindle. The energy cycles of the cell, how molecules work to produce motion in some very fine-grade structures like cilia in the human windpipe, and their role in communicating nerve messages - all are covered in just enough detail to explain without confusing. Ball's last chapter - on molecular computing - have been somewhat overtaken by events in a rapidly-moving field (it's now possible to store data on DNA, for example), but don't let that put you off. This is, and will I suspect remain, a first-class introduction to this fascinating subject for some time to come.