Control of distributions provides a more direct paradigm to deal with the uncertainties in dynamical systems compared with the standard optimal control approach. In this talk I will give an overview of the distribution/density control problems for control-affine systems. A reformulation as an optimization over distributions will be presented and its connections to the Schrodinger bridge problems will be discussed. We will also discuss the covariance steering problem, which is a special type of density control problems when the marginal distributions are Gaussian. Both linear and nonlinear settings will be covered.