  It is known that the expectation value of Wilson loops in the
Gross-Witten-Wadia (GWW) unitary matrix model can be computed exactly at finite
$N$ for arbitrary representations. We study the perturbative and
non-perturbative corrections of Wilson loops in the $1/N$ expansion, either
analytically or numerically using the exact result at finite $N$. As a
by-product of the exact result of Wilson loops, we propose a large $N$ master
field of GWW model. This master field has an interesting eigenvalue
distribution. We also study the Wilson loops in large representations, called
Giant Wilson loops, and comment on the Hagedorn/deconfinement transition of a
unitary matrix model with a double trace interaction.
