The Igth century was distinguished by the construction of machines with enormous power. During the last decade rapid progress has been made in the development of a completely different type of machine. These new machines, the electronic computers, are not built to generate power or to do mechanical work, but to perform logical operations and ca1culations. This new concept will have a profound influence on engineering, science, ami economy. In fact, the first effects of this development are already taking shape today. It is the purpose 01 this book to give a survey of the basic principles and applications of computers for the benefit of those who hitherto did not work with them, but who might have use for them in the future. The rapid progress of the engineering science has, naturally, led to a situation in which the practicing scientist and engineer cannot keep abreast of the progress in neighboring fields. The chapters of this book were prepared by distinguished experts in the field of computers for the non-expert who does not intend to become an expert, but W}: l0 wants Jo acquire a general understanding of the problems and solutions which he needs to effectively perform the work in his proper field. We address this book to the engineers and scientists who want to know the performance of computers, as weH as to the managers who are rnainly concerned with their econornic aspect.