  Analytic versions of QCD are those whose coupling alpha_s(Q^2) does not have
the unphysical Landau singularities on the space-like axis (-q^2=Q^2 > 0). The
coupling is analytic in the entire complex plane except the time-like axis (Q^2
< 0). Such couplings are thus suitable for application of perturbative methods
down to energies of order GeV. We present a short review of the activity in the
area which started with a seminal paper of Shirkov and Solovtsov ten years ago.
Several models for analytic QCD coupling are presented. Strengths and
weaknesses of some of these models are pointed out. Further, for such analytic
couplings, constructions of the corresponding higher order analytic couplings
(the analogs of the higher powers of the perturbative coupling) are outlined,
and an approach based on the renormalization group considerations is singled
out. Methods of evaluation of the leading-twist part of space-like observables
in such analytic frameworks are described. Such methods are applicable also to
the inclusive time-like observables. Two analytic models are outlined which
respect the ITEP Operator Product Expansion philosophy, and thus allow for an
evaluation of higher-twist contributions to observables.
