The document discusses the life and contributions of a Russian theorist born in 1896, who emphasized the impact of social interactions and language on cognitive development, coining the socio-cultural theory of development. It highlights the importance of scaffolding in learning, where adults and peers support children in tasks that they cannot perform independently, facilitating their movement from the zone of actual development to the zone of proximal development. The document underlines how effective learning occurs through participation and guidance in social activities, influenced by cultural context.