Chapters - Arithmetic in Z Revisited - Congruence in Z and Modular Arithmetic - Rings - Arithmetic in f(x) - Congruence in f(x) and congruence-class arithmetic - Ideals and quotien rings - Groups - Topics in group theory - Arithmetic in integral domains - Field extensions - Galois theory - Public-key cryptography - The chinese remainder theorem - Lattices and boolean algebras - Geometric constructions - Algebraic coding theory - Appendices - Answers ans suggestions