Clicker training (also known as magazine training) is a method for training animals that uses positive reinforcement in conjunction with a clicker, or small mechanical noisemaker, to mark the behavior being reinforced. The clicker is used during the acquisition phase of training a new behavior, to allow the animal to rapidly identify the precise behavior of interest.
Clicker training originated with Marian Bailey (née Kruse) and Keller Breland, who as graduate students of psychologist and eminent behaviorist B.F. Skinner taught wild-caught pigeons to "bowl" (push a ball with their beaks) during military research.[1] According to their work, animal training was being needlessly hindered because traditional methods of praise and reward did not inform the animal of success with enough promptness and precision to create the required cognitive connections for speedy learning. Similar methods were later used in training at least 140 species including whales, bears, lions, chickens and domestic dogs and cats, and even humans

from-http://en.wikipedia.org/wiki/Clicker_training