  We review recent studies of the operator product expansion of the plaquette
and of the associated determination of the gluon condensate. One first needs
the perturbative expansion to orders high enough to reach the asymptotic regime
where the renormalon behavior sets in. The divergent perturbative series is
formally regulated using the principal value prescription for its Borel
integral. Subtracting the perturbative series truncated at the minimal term, we
obtain the leading non-perturbative correction of the operator product
expansion, i.e. the gluon condensate, with superasymptotic accuracy. It is then
explored how to increase such precision within the context of the
hyperasymptotic expansion. The results fully confirm expectations from
renormalons and the operator product expansion.
