Roger Brown was an influential American psychologist known for his work in the field of language development and social psychology. He is best recognized for his research on the acquisition of language in children, particularly his studies on morphemes and syntax. His findings contributed significantly to our understanding of how children learn to communicate. In addition to his work on language, Roger Brown also explored the concept of self-concept and how individuals perceive themselves in social contexts. His research has had a lasting impact on both psychology and education, shaping approaches to teaching language and understanding social behavior in children.