Transverse momentum resummation generalizes the conventional collinear factorization for hadronic processes to calculate both normalization and shape of particle distributions. Since its conception in the late 1970's, QT resummation has been successfully applied to study all-order structure of hadronic differential distributions and provide excellent predictions for a variety of experiments. Analytical resummation should not be confused with Monte-Carlo showering models, which have different objectives, strengths, and weaknesses. In fact, QT resummation and parton showering methods are quite complementary, as shown by the comparison of their key features.