Part I: General Basic Theory: Algebraic Integers. Completions. The Different and Discriminant. Cyclotomic Fields. Paralellotopes. The Ideal Function. Ideles and Adeles. Elementary Properties of the Zeta Function and L-series.- Part II: Class Field Theory: Norm Index Computations. The Artin Symbol, Reciprocity Law, and Class Field Theory. The Existence Theorem and Local Class Field Theory. L-series Again.- Part III: Analytic Theory: Functional Equation of the Zeta Function, Hecke''s Proof. Functional Equation, Tate''s Thesis. Density of Primes and Tauberian Theorem. The Brauer-Siegel Theorem. Explicit Formulas.- Bibliography.- Index.