  We review recent results from the RHIC beam energy scan (BES) program, aimed
to study the Quantum Chromodynamics (QCD) phase diagram. The main goals are to
search for the possible phase boundary, softening of equation of state or first
order phase transition, and possible critical point. Phase-I of the BES program
has recently concluded with data collection for Au+Au collisions at
center-of-mass energies ($\sqrt{s_{NN}}$) of 7.7, 11.5, 19.6, 27, and 39 GeV.
Several interesting results are observed for these lower energies where the
net-baryon density is high at the mid-rapidity. These results indicate that the
matter formed at lower energies (7.7 and 11.5 GeV) is hadron dominated and
might not have undergone a phase transition. In addition, the centrality
dependence of freeze-out parameters is observed for the first time at lower
energies, slope of directed flow for (net)-protons measured versus rapidity
shows an interesting behavior at lower energies, and higher moments of
net-proton show deviation from Skellam expectations at lower energies. An
outlook for the future BES Phase-II program is presented and efforts for the
detailed study of QCD phase diagram are discussed.
