Preface. 1. Groups. 2. Rings, Modules and Algebras. 3. Group Rings. 4. A Glance at Group Representations. 5. Group Characters. 6. Ideals in Group Rings. 7. Algebraic Elements. 8. Units of Group Rings. 9. The Isomorphism Problem. 10. Free Group of Units. 11. Properties of the Unit Group. Bibliography. Index.