This document discusses psycholinguistics and language acquisition. It addresses the general issues of psycholinguistics including language acquisition, production, comprehension, and the relationship between language and thought. It then focuses on first and second language acquisition. It describes two notions in first language acquisition: overgeneralization and undergeneralization. Some examples of each are provided. Reasons for overgeneralization and undergeneralization are discussed. Stages of first language acquisition are outlined. The document concludes by discussing whether children are better than adults at learning a second language and comparing natural and classroom settings for second language learning.