MongoDB is a document database that provides high performance, high availability, and easy scalability, since it is an unstructured data and doesn't require costly and time-consuming migrations when we want to change our schema dynamically . MongoDB's documents are encoded in a JSON-like format, called BSON, which makes storage easy, is a natural fit for modern object-oriented programming methodologies, and is also lightweight, fast and traversable.
In addition, MongoDB supports N number of feathers that are:
MongoDB's document data model makes it easy to build on, since it supports unstructured data natively and doesn't require costly and time-consuming migrations when application are encoded in a JSON-like format, called BSON, which makes storage easy.
Rich queries and full indexes, distinguishing it from other document databases that make complex queries difficult or require a separate server layer to enable them.
Difference Between Document Data Model and Relational Data Model
Here In above image you can see that how Document Data Model is more useful