In the Standard Model, there are three independent parameters for the electroweak sector.
In the context of the electroweak corrections for LHC processes, the most common choices of independent electroweak parameters
are $(G_\mu,M_W,M_Z)$ and $(\alpha(M_Z),M_W,M_Z)$, but many other choices are possible. Though, at a given order in perturbation
theory, all schemes are formally equivalent, the corresponding numerical predictions differ because of the truncation of the
perturbative expansion. It is thus important to know the strengths and the weaknesses of the possible input parameter schemes
in order to choose the most suited for the calculation at hand.