ABSTRACT
This chapter deals with the nature of the input to second language (L2) learners, feedback to learners, and language production output. It focuses on the interrelationship of L2 use especially conversation and language learning. The chapter begins the chapter with a description of the major components of what has been referred to as the Interaction Hypothesis, or more recently as the interaction approach: input, comprehension, interaction, output, and feedback. It then turns to the role of these components in language learning and considers the complexity involved when it begin to think about who benefits from interaction and why. Crucial to the success of any conversation is the ability to understand and to be understood. Lack of comprehension is a characteristic of many conversations involving NNSs. Interaction has been dealt with in second language acquisition (SLA) from a variety of perspectives, for example, psycholinguistically and from a variationist perspective.
