2 of the photon to the lowest values of x yet, where the hadronic component of the photon is most important. Inclusive cross sections for D-mesons have been measured as a function of their transverse momenta and are used to test the validity of perturbative QCD in NLO in this region. The total charm quark production cross section is extracted. For the first time the inclusive production of D me...

The production of lepton pairs in hadron collisions h1h2 → γX ; γ → ll̄ proceeds through an intermediate virtual photon via qq̄ → γ, and the subsequent leptonic decay of the virtual photon. Interest in this Drell-Yan process is usually focussed on lepton pairs with large mass Q which justifies the application of perturbative QCD and allows for the extraction of the antiquark density in hadrons [ ...

Some general considerations on a future linear collider and selected topics of two photon physics measurements which can be performed at such a collider are presented. This review discusses the total photon-photon cross section, jet cross sections, structure functions, charm production, the BFKL Pomeron, W pair production, and Higgs production.