In this survey, we study deformations of finitely generated groups into Lie groups, focusing on the case underlying convex projective structures on manifolds and orb-ifolds, with an excursion on projective structures on surfaces. We survey the basics of the theory of deformations, (G, X)-structures on orbifolds, Hilbert geometry and Coxeter groups. The main examples of finitely generated groups for us will be Fuchsian groups, 3-manifold groups and Coxeter groups.