Behaviourism was an influential theory of learning in the 1940s-1950s that viewed language development as the formation of habits through imitation and practice. B.F. Skinner's work with operant conditioning chambers demonstrated that behaviors are shaped through reinforcement or discouragement. Traditional behaviourism hypothesized that children learn language by imitating others and being positively reinforced through praise for their attempts. The environment plays a key role by providing consistency in reinforcement to shape a child's language behaviors.