The history of the tractor is one of short, rapid development, from the turn of the century when it was seen as little more than a substitute for the horse, to today's sophisticated machines that boast a host of technologically advanced equipment. This unique, visual guide charts that fascinating history and also provides an A -- Z reference from around the world. Each piece of machinery is illustrated with archive black and white or full color photography, and the informative text includes specification boxes and a detailed mechanical profile.