W and Z production: cross sections and asymmetries

The LHC will be a W and Z factory. At nominal low luminosity of L=$10^{33} \mbox{cm}^{-2}\mbox{s}^{-1}$ approx 15 W$\rightarrow \mbox{l}\nu$ events and 1.5 Z$\rightarrow$ll, l$=\mu,$e events will be produced per second. These processes will be important to test the Standard Model via precision measurements. W and Z production represent backgrounds to other Standard Model processes and signals of new physics and thus need to be understood precisely in the new kinematic region available at the LHC. In addition, they will be crucial physics channels to understand the detectors and its performances at start-up.