Introduction to the Symmetry Breaking Sector *

The basic ingredients of the Spontaneous Symmetry Breaking Phenomenon and of the Higgs Mechanism are reviewed in these lectures of pedagogical character. Some relevant topics related with the breaking SU(2) L × U(1) Y → U(1) em are selected and discussed here. A brief survey of the experimental Higgs particle searches and the theoretical limits on M H are also presented. The main features of the most popular models of symmetry breaking beyond the Standard Model are briefly considered. It includes a short summary of the Higgs Sector in the Minimal SUSY Model, the basic ideas of Technicolor models and a brief introduction to Strongly Interacting Scalar sectors and to the Effective Chiral Lagrangian Approach to the Electroweak Theory.