The phase structure of QCD

We review recent results on the phase structure of QCD and bulk QCD\nthermodynamics. In particular we discuss how universal critical scaling related\nto spontaneous breaking of the chiral symmetry manifests itself in recent\nlattice QCD simulations and how the knowledge on non-universal scaling\nparameter can be utilized in the exploration of the QCD phase diagram. We also\nshow how various (generalized) susceptibilities can be employed to characterize\nproperties of QCD matter at low and hight temperatures, related to deconfining\naspects of the QCD transition. Finally, we address the input these lattice QCD\ncalculation can provide for our under standing of the matter created in heavy\nion collisions and in particular on the freeze-out conditions met in the\nhydrodynamic evolution of this matter.