Higgs Mechanism

The Higgs mechanism: gauge bosons acquire mass by "eating" the Goldstone boson from spontaneous symmetry breaking.
W mass: M_W = gv/2; Z mass: M_Z = M_W/cos(θ_W); photon stays massless (unbroken U(1)_EM).
Yukawa coupling: fermion mass m_f = y_f·v/√2 — the Higgs couples to fermion pairs, stronger for heavier fermions.
The actual Higgs boson (discovered ATLAS/CMS 2012, m_H ≈ 125.09 GeV) is the radial excitation of the Higgs field around its VEV.