Vygotsky's socio-cultural theory posits that social interaction and cultural factors play a key role in cognitive development. Vygotsky believed development occurs through interactions children have with others in cultural contexts. He emphasized the importance of language and scaffolding, where adults provide appropriate assistance to help children accomplish tasks. Vygotsky's theory contrasts with Piaget's view that development occurs through individual, universal stages by stressing social and cultural influences on thinking.