Few theorems in the history of mathematics have acquired the almost legendary status that quadratic reciprocity holds in number theory. First conjectured by Euler, it provides a striking relationship between the primes in terms of the solvability of certain quadratic congruences and has become a cornerstone of elementary number theory. The great Carl Friedrich Gauss was the first one to provide a valid proof and liked it so much that he called it his "aureum theorema" (golden theorem) and provided no less than 8 different proofs during his lifetime.