The forward photon production and the gluonic content of the real and virtual photon at the HERA collider

The discussion on the production of prompt photons with pT of a few GeV in the tagged process ep -> e gamma X with small Q^2 (DIC process) at the HERA collider is presented. Photons produced in the forward (proton) direction are mainly originating from subprocesses involving interactions of the gluonic content of the exchanged photon. The large enhancement over the Born term (direct photon) is found up to a factor of 35 for a real photon and up to 5 for a virtual photon with a squared virtuality 1 GeV^2. It gives a possibility of extracting a gluonic density of the real and of the virtual photon. The BFKL approach to the description of the forward particle production is shortly discussed.