جان بی. واتسون (John B. Watson) was an American psychologist who is best known for founding the school of behaviorism. He believed that psychology should focus on observable behaviors rather than internal mental states. His work emphasized the importance of environmental factors in shaping behavior, leading to the idea that all behaviors are learned through interaction with the environment. Watson's most famous experiment involved a young boy named Little Albert, where he demonstrated that emotional responses could be conditioned. His theories laid the groundwork for later developments in psychology, influencing fields such as behavioral therapy and educational psychology.