This document summarizes several theories of language acquisition, including: - Behaviorism (Skinner): Children imitate adults and language is acquired through reinforcement. - Cognitive (Piaget): Language develops as one part of a child's overall cognitive development. - Innateness (Chomsky): Language ability is innate and guided by a language acquisition device and universal grammar. - Interactionism (Bruner): Both innate abilities and interactions with caretakers in early childhood support language acquisition.