Lev Vygotsky', a Soviet psychologist, has propounded the "Socio-cultural Theory". This theory implies the idea that social interaction plays a crucial role in the development of learners' cognitive ability. Vygotsky has proposed the concept of 'Zone of Proximal Development (ZPD)' in his theory which refers to the difference between what a learner can do on his/her own and what he/she can do with someone's help.It is a distance between the learner's actual development level and his/her level of development under someone's guidance.In the concept of the Zone of proximal development, the term Proximal indicates that the assistance provided should be just beyond learners' current competence.It emphasizes putting comprehensible input slightly above the learner's current level so that they could complete the task effectively.Hence it could be concluded that in the concept of Zone of proximal development proposed by Lev Vygotsky, the term Proximal indicates that the assistance provided goes just beyond learners' current competence.Additional InformationOther Important Terms Proposed by Vygotsky in his 'Socio-cultural Theory':Scaffolding: It refers to a process through which temporary support is imparted to the learners to enhance learning to achieve goals.More Knowledgeable Other(MKO): It refers to a person with a higher skill level and a better understanding of the concepts than the learners.