Quark and gluon structure of the nucleon

Recently deep inelastic physics in the very low Bjorken x region has made significant progress due to the large kinematical region covered by the HERA experiments by now. Stringent tests of perturbative QCD predictions on the evolution of the parton density functions in the nucleon are possible over 5 (4) orders of magnitude in x (Q2). Newer results from structure function studies on scaling violations, the charm contribution and the effect of longitudinally polarized virtual photons give a consistent picture of a strongly rising gluon density distribution towards low x. Some aspects of the search for an indication of BFKL like behaviour in the low x regime are presented and data covering the region at low Q2 are shown, where perturbative QCD is believed to be no longer valid.--This contribution concentrates on HERA results, but other data are also taken into account where appropriate. In a second part the events observed at HERA in excess over the standard model prediction at very high Q2 are discussed