CRUD stands for create, read, update, and delete, which are the four core database operations used in database driven application development. The CRUD Operations for MongoDB section provides introduction to each class of operation along with complete examples of each operation. The documents in the Read and Write Operations in MongoDB section provide a higher level overview of the behavior and available functionality of these operations.
The Read Operations and Write Operations documents provide higher level introductions and description of the behavior and operations of read and write operations for MongoDB deployments. The BSON Documents provides an overview of documents and document-orientation in MongoDB.