MongoDB is a document database that stores data in JSON-like documents. It is a cross-platform, document-oriented database program created by MongoDB Inc. and is distributed under the Server Side Public License (SSPL). MongoDB boasts several notable features, including support for field and range queries as well as regular expression searches. Queries in MongoDB can target specific document fields and incorporate user-defined JavaScript functions. Additionally, they can be customized to return a random sample of results of a specified size.