Hadron structure functions

Among the most challenging issues of the strong interaction is the understating of the structure of hadrons, the subject of the non perturbative Quantum
Chromodynamics (QCD). Nucleon structure observables like the electromagnetic form factors, the generalised and transition distribution amplitudes (GDA,
TDA), and the parton distribution functions (PDF) have been the subject of intensive theoretical and experimental studies.  Despite the large amount of
available data and the significant progress in the  experimental techniques, the structure of hadrons still presents many challenges. The complexity of
these amplitudes requires a large variety of complementary experiments, techniques and probes in order to reach a full understanding and a complete
picture of hadrons. In this talk, the investigation of the hadron structure aspects related to the possibilities offered by the scattering experiments,
the proton-antiproton and the electron-positron facilities, are reported.  A special emphasis is given to the exciting prospects of the future antiproton
beams of FAIR, in the high momentum range between 1.5 and 15 GeV/c.