  Recent progress in the understanding of the nucleon is presented. The
unpolarised structure functions are obtained with unprecedented precision from
the combined H1 and ZEUS data and are used to extract proton parton
distribution functions via NLO QCD fits. The obtained parametrisation displays
an improved precision, in particular at low Bjorken x, and leads to precise
predictions of cross sections for LHC phenomena. Recent data from
proton-antiproton collisions at Tevatron indicate further precise constraints
at large Bjorken x. The flavour content of the proton is further studied using
final states with charm and beauty in DIS ep and pp collisions. Data from
polarised DIS or proton-proton collisions are used to test the spin structure
of the proton and to constrain the polarised parton distributions.
