NoSQL, meaning "not only SQL," refers to a type of database that provides a mechanism for storage and retrieval of data that is modeled in means other than the tabular relations used in relational databases. NoSQL databases are particularly useful for working with large sets of distributed data. They are known for their flexibility, as they allow for the storage of data in a format that does not require a predefined schema, and are often used for big data and real-time web applications. They offer a variety of data models, including document, graph, key-value, and wide-column stores.
