This is a very popular method used in teaching preschool children. New words, phrases and constructions are remembered with the help of gestures, pantomime and games. Thus, kids can learn a lot of words by associating them to moves or pictures.
Young learners are not able to translate. Their thinking pattern is mostly visual. To remember a new word, a child needs to connect it to its image or a gesture. And this is how TPR method works.