with the increasing interest in applying the methodology of difference-of-convex (dc) optimization to diverse problems in engineering and statistics, we show that many well-known functions arising therein can be represented as the difference of two convex functions. these include a univariate folded concave function commonly employed in statistical learning, the value function of a copositive recourse function in two-stage stochastic programming, and many composite statistical functions in risk analysis, such as the value-at-risk (var), conditional value-at-risk (cvar), expectation-based, var-based, and cvar-based random deviation functionals. we also discuss decomposition methods for computing directional stationary points of a class of nonsmooth, nonconvex dc programs that combined the gauss-seidel idea, the alternating direction method of multipliers, and a special technique to handle the negative of a pointwise max function.