%0 Journal Article %T QCD Thermodynamics with 2 and 3 Quark Flavors %A F. Karsch %A E. Laermann %A A. Peikert %A Ch. Schmidt %A S. Stickan %J Physics %D 2000 %I arXiv %X We discuss the flavor dependence of the pressure and critical temperature calculated in QCD with 2, 2+1 and 3 flavors using improved gauge and staggered fermion actions on lattices with temporal extent Nt=4. For T > 2 Tc we find that bulk thermodynamics of QCD with 2 light and a heavier strange quark is well described by 3-flavor QCD while the transition temperature is closer to that of 2-flavor QCD. Furthermore, we present evidence that the chiral critical point of 3-flavor QCD, i.e. the second order endpoint of the line of first order chiral phase transitions, belongs to the universality class of the 3d Ising model. %U http://arxiv.org/abs/hep-lat/0010027v1