MongoDB as the most popular NoSQL database is a source-available cross-platform document-oriented database program. It uses JSON-like documents with optional schemas and it is popular because of the ease with which data can be stored and retrieved.
MongoDB Introduction
MongoDB uses documents that contain a data structure composed of field and value pairs to store data so Documents are the basic unit of data in MongoDB. The documents are similar to JavaScript Object Notation, but use a variant called Binary JSON (BSON). BSON helps to have more data types and that is why MongoDB uses it. The overall terminology in MongoDB and RDBMS are similar and there are some small differences.
Database
The database is the container for collections. It has its own sets of files on the file system and a single MongoDB instance can have multiple databases.
