Hello all I hope you can help me with this query. I would like to find an introductory text in extra dimensions. I am taking a course in BSM and I have been referred to: C. Csaki, TASI lectures on extra dimensions and branes, hep-ph/0404096, but I was hoping to find something more introductory. The material I'm hoping to find (what was covered in the lectures) is: KK-reduction (scalar field) Compactification on an interval (orbifold S1/Z2) Interactions (briefly. How does the phi fourth and phi cube couplings look like in 4D) Gauge fields (how you can get a scalar from a gauge field) Fermions in 5D (how to get a chiral theory in 4D). Large extra dimensions I specially have trouble assimilating the orbifold concept and the gauge fields parts. Do you know any text I can use to backup my notes? Thank you for your attention. Regards.