Euclidean Algorithm. Greatest common divisor, Euclid, Extended Euclidean algorithm, Euclidean domain, Continued fraction, Gabriel Lame, Modulo operation, Division algorithm, Johann Peter Gustav Lejeune Dirichlet, Richard Dedekind, Fermat's theorem on sums of two squares, Bezout's identity, Diophantine equation, Modulo operation, Division algorithm, Johann Peter Gustav Lejeune Dirichlet, Richard Dedekind, Fermat's theorem on sums of two squares, Bezout's identity, Diophantine equation