  Hadron correlations in jets, ridges and opposite dijets at all $p_T$ above 2
GeV/c are discussed. Since abundant data are available from RHIC at
intermediate $p_T$, a reliable hadronization scheme at that $p_T$ range is
necessary in order to relate the semihard partonic processes to the
observables. The recombination model is therefore first reviewed for that
purpose. Final-state interaction is shown to be important for the Cronin
effect, large B/M ratio and forward production. The effect of semihard partons
on the medium is then discussed with particular emphasis on the formation of
ridge with or without trigger. Azimuthal anisotropy can result from ridges
without early thermalization. Dynamical path length distribution is derived for
any centrality. Dihadron correlations in jets on the same or opposite side are
shown to reveal detail properties of trigger and antitrigger biases with the
inference that tangential jets dominate the dijets accessible to observation.
