Diffractive structure functions in DIS

A review of theoretical models of diffractive structure functions in deep inelastic scattering (DIS) is presented with a view to highlighting distinctive features, that may be distinguished experimentally. In particular, predictions for the behaviour of the diffractive structure functions $F_2^D, F_L^D, F_2^{D(\mbox{\small{charm}})}$ are presented. The measurement of these functions at both small and high values of the variable $\beta$ and their evolution with $Q^2$ is expected to reveal crucial information concerning the underlying dynamics.