Abstract
<jats:title>Abstract</jats:title> <jats:p>An online corpus is a structured digital collection of texts accessible via the Internet, widely used in linguistic research and language studies. Online corpora can be general, specialized, or parallel, supporting areas such as discourse analysis, sociolinguistics, language teaching and learning, and lexicography. They differ from offline corpora, which are stored locally and provide greater control over data but lack the accessibility and frequent updates of online resources. Some corpora, such as COCA and NOW, are monitor corpora, regularly updated to capture ongoing changes in language use. Online corpora also vary in design: some are primarily research‐oriented, offering advanced search and analysis tools (e.g., Sketch Engine, AntConc, #LancsBox), while others are platforms with a pedagogical focus, providing user‐friendly access to corpora and tools for students and teachers (e.g., SkELL, CorpusMate). Their advantages include accessibility, scope, diversity, and integrated analytical tools; limitations include dependence on Internet connectivity and reduced control over content. Online corpora have significantly influenced both theoretical and applied linguistics, contributing to dictionary design, the development of teaching materials, and feedback in language learning. This entry introduces the main types, uses, advantages, and limitations of online corpora, situating them within the broader field of corpus linguistics.</jats:p>