2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/38141Recent measurements of unpolarised and polarised nucleon structure functions and F_2(gamma) are reviewed. The implications for QCD and the gluon momentum distribution are discussed. The status of the understanding of the total virtual-photon proton total cross-section in the transition region between real photoproduction and deep-inelastic scattering is summarised briefly.Extended version of writeup of plenary talk at EPS HEP97 Jerusalem. LaTeX 20 pages, 13 figures. Uses psfig and prhep97.styHigh Energy Physics - Experimenttext