The Grand Unified Theories: SU(5), and SO(10), etc Unification of the gauge interactions, and unifications of the SM fermions Charge quantization Gauge coupling unification in the MSSM, and Yukawa unification 犹t=b=y Radiative electroweak symmetry breaking due to the large top quark Yukawa coupling e Weak mixing angle at weak scale Mz Neutrino masses and mixings by seesaw mechanism