A "corpus" is a large collection of written or spoken texts used for linguistic research and analysis. These texts can include books, articles, conversations, and other forms of communication. Researchers use corpora to study language patterns, vocabulary, grammar, and usage in different contexts. Corpora can be specialized, focusing on specific subjects like medicine or law, or they can be general, representing a wide range of language use. They are essential tools for linguists, language learners, and software developers working on applications like natural language processing and machine translation.