This paper systematically surveys useful properties of the epigraph reformulation for optimization problems, and complements them by some new results. We focus on the complete compatibility of the original formulation and the epigraph reformulation with respect to solvability and unsolvability, the compatibility with respect to some, but not all, basic constraint qualifications, the formulation of first order optimality conditions for problems with max-type objective function, and the interpretation of feasibility and optimality cuts along epigraphs in the framework of cutting plane methods. Finally we introduce a generalized epigraph reformulation which is particularly useful for treating summands of objective and constraint functions independently in the reformulation.