  We present results from our simulations of quantum chromodynamics (QCD) with
four flavors of quarks: u, d, s, and c. These simulations are performed with a
one-loop Symanzik improved gauge action, and the highly improved staggered
quark (HISQ) action. We are generating gauge configurations with four values of
the lattice spacing ranging from 0.06 fm to 0.15 fm, and three values of the
light quark mass, including the value for which the Goldstone pion mass is
equal to the physical pion mass. We discuss simulation algorithms, scale
setting, taste symmetry breaking, and the autocorrelations of various
quantities. We also present results for the topological susceptibility which
demonstrate the improvement of the HISQ configurations relative to those
generated earlier with the asqtad improved staggered action.
