Asymmetries at the Z pole: The Quark and Lepton Quantum Numbers

The impressive progress on the knowledge of lepton and quark electroweak couplings over the LEP and SLC decade is reviewed. The experimental methods for measuring the forward-backward asymmetry of charged-fermion pair-production are described, for different fermion species. The precise measurements of the left–right asymmetry and of tau polarisation at the Z resonance are also reminded. After discussing the determination of the Weinberg electroweak mixing angle, lepton and quark couplings are extracted by combining asymmetry and polarisation measurements with measurements of partial decay widths of the Z boson, performed at LEP in the same years.