Descriptive grammar is the study of how language is actually used by speakers and writers in real-life situations. It focuses on the rules and patterns that emerge from everyday communication, rather than prescribing how language should be used. This approach recognizes that language is dynamic and can vary based on factors like region, social group, and context. Unlike prescriptive grammar, which sets strict rules for correct usage, descriptive grammar aims to document and analyze the natural variations in language. It helps linguists understand the complexities of human communication and the ways in which languages evolve over time, reflecting cultural and social changes.