  Recently the ATLAS and CMS experiments at the LHC have found a Higgs like
boson $h$ with a mass around 125 GeV from several decay modes. The decay mode
$h \to \gamma\gamma$ is one of the most important modes in studying whether $h$
is actually the standard model (SM) Higgs boson. Current data indicate that
$h\to \gamma\gamma$ has a branching ratio larger than the SM prediction for $h$
being identified as the SM Higgs boson. To decide whether the $h$ discovered at
the LHC is the SM Higgs boson, more data are needed. We study how
$\gamma\gamma$ collider can help to provide some of the most important
information about the Higgs boson properties. We show that a $\gamma\gamma$
collider can easily verify whether the enhanced $h \to \gamma\gamma$ observed
at the LHC hold. Different models can be tested by studying Higgs boson decay
to $\gamma Z$. Studying angular distribution of the $\gamma \gamma$ through
on-shell production of $h$ and its subsequent decays into a $\gamma \gamma$
pair can decide whether the Higgs like boson $h$ at the LHC is a spin-0 or a
spin-2 boson.
