Is what communists (although it has happened in other countries, including the U.S. to a limited extent) give people who do not follow the party line. It mainly involves a constant barrage of propaganda - but has also been known to include forced labor, torture and drugs - in order to cause brainwashing.

A good visual, although not necessarily realistic, depiction of reeducation can be found in Stanley Kubric's film "A Clock Work Orange."