  This paper is an updated version of the lectures given at the XXIX
International Meeting on Fundamental Physics in Sitges, Barcelona (February
2000). The measurements perforned at LEP and SLC have substantially improved
the precision of the test of the Minimal Standard Model. The precision is such
that there is sensitivity to pure weak radiative corrections. This allows to
indirectly determine the top mass (m_t = 180 +- 10GeV), the W-boson mass (M_W =
80.375 +- 0.022GeV), and to set an upper limit on the Higgs boson mass of
196GeV at 95% confidence level.
