  The first run of the Large Hadron Collider at CERN brought the discovery of
the Higgs boson, an apparently elementary scalar particle with a mass of 125
GeV, the avatar of the mechanism that hides the electroweak symmetry. A new
round of experimentation is beginning, with the energy of the proton--proton
colliding beams raised to 6.5 TeV per beam, from 4 TeV at the end of the first
run. This article summarizes what we have learned about the Higgs boson, and
calls attention to some issues that will be among our central concerns in the
near future.
