The purpose of this book is to cover, in a mathematically precise manner, a variety of concepts, results, techniques, and applications of modern algebra that are of particular use to beginning students in the computer sciences. Abstract topics such as sets, relations, functions, Boolean algebras, groups, rings, and fields are interspersed in this book with computer-oriented applications such as combinational and sequential networks, formal languages, automata, and codes. The object of this interspersal is to provide the beginner with motivation for delving into abstract mathematics, and to lay the groundwork for a number of applied areas which, as a computer-sciences major, the student will pursue in the future.