Structure Functions for the Virtual and Real Photons
  Development of concepts related to the photon and its high energy hadronic interaction is briefly reviewed. A photon considered as an ideal probe of hadron structure, paradoxically is also considered as an ideal target to test the perturbative QCD. The present status of the theoretical and experimental analysis of the structure functions for a virtual and real photon is presented. 
Maria Krawczyk (Institute of Theoretical Physics, University of   Warsaw, Poland)