This document provides an introduction to the field of linguistics and psycholinguistics. It defines linguistics as the science that studies human language and notes that language can be studied from various perspectives including linguistics, psycholinguistics, and neurolinguistics. Psycholinguistics is defined as the study of language from a psychological perspective, with the goals of understanding how people acquire, use, and process language in the brain. The document discusses some key aspects of language including that it is symbolic, voluntary, and systematic, and can take different modalities like spoken, written, and signed forms.