  This write-up of lectures given at TASI 2020 provides an introduction into
precision tests of the electroweak Standard Model. The lecture notes begin with
a hands-on review of the (on-shell) renormalization procedure, and subsequently
highlight a few subtleties that occur in the renormalization of a theory with
electroweak symmetry breaking and massive gauge bosons. After that a set of
typical electroweak precision observables is introduced, as well as a range of
input parameter measurements that are needed for making predictions within the
Standard Model. Finally, it is discussed how comparisons of the electroweak
precision observables between experiment and theory can be used to stress-test
the Standard Model and probe new physics.
