2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/55707This is an elementary introduction to Wilson renormalization group and continuum effective field theories. We first review the idea of Wilsonian effective theory and derive the flow equation in a form that allows multiple insertion of operators in Green functions. Then, based on this formalism, we prove decoupling and heavy-mass factorization theorems, and discuss how the continuum effective field theory is formulated in this approach.23 pages, RevTeX, Lecture presented at The 11th Summer School and Symposium on Nuclear Physics (NuSS'98), Seoul National University, June 23-26, 1998, KoreaHigh Energy Physics - Theorytext