  Results for the equation of state in 2+1 flavor QCD at zero net baryon
density using the Highly Improved Staggered Quark (HISQ) action by the HotQCD
collaboration are presented. The strange quark mass was tuned to its physical
value and the light (up/down) quark masses fixed to $m_l = 0.05m_s$
corresponding to a pion mass of 160 MeV in the continuum limit. Lattices with
temporal extent $N_t=6$, 8, 10 and 12 were used. Since the cutoff effects for
$N_t>6$ were observed to be small, reliable continuum extrapolations of the
lattice data for the phenomenologically interesting temperatures range $130
\mathord{\rm MeV} < T < 400 \mathord{\rm MeV}$ could be performed. We discuss
statistical and systematic errors and compare our results with other published
works.
