Zone of Proximal Development (ZPD): The distance between what a learner can do alone and what they can achieve with the guidance of a "More Knowledgeable Other" (MKO).
Scaffolding: Temporary support structures (clues, encouragement, simplified steps) provided by a teacher to help a student master a task.
Private Speech: The "self-talk" children use to guide their own thinking; Vygotsky viewed this as the transition from social talk to internal thought.
Mediation: The use of tools (language, signs, symbols) to bridge the gap between the individual and the environment.
