For different points of view, the reader is encouraged to read the collec tion of papers from the Brighton Symposium (edited by Cassels-Frohlich), the Artin-Tate notes on class field theory, Weil’s book on Basic Number Theory, Borevich-Shafarevich’s Number Theory, and also older books like those of W eber, Hasse, Hecke, and Hilbert’s Zahlbericht.