Holographic methods and gauge-Higgs unification in flat extra dimensions

I review the holographic techniques used to efficiently study models with gauge-Higgs unification (GHU) in one extra dimension. The general features of GHU models in flat extra dimensions are then reviewed, emphasizing the aspects related to electroweak symmetry breaking. Two potentially realistic models, based on SU(3) and SO(5) electroweak gauge groups, respectively, are constructed.