Any person (or even technology) with a greater understanding of a task than the learner. This could be a teacher, parent, or a highly skilled peer.

The "magic" space where learning occurs, defined as the distance between what a student can do independently and what they can achieve with the guidance of a more experienced partner.

Cultures provide "tools of intellectual adaptation"—such as language, counting systems, and art—that shape how children think and solve problems in ways relevant to their specific environment. The Role of Culture in Learning Vygotsky's Educational Theory in Cultural Context