Linguistics is the scientific study of language. It has two main purposes: to study the nature and rules of language, and to understand how language is organized and functions in human life. The document discusses key topics in linguistics including the main branches of linguistics, which are divided into microlinguistics focusing on language itself, and macrolinguistics examining language in relation to other areas. It also distinguishes between descriptive linguistics, which analyzes actual language use, and prescriptive linguistics, which prescribes rules for "correct" language behavior.