MongoDB is an open source database management system (DBMS) that uses a document-oriented data model. It is used by some of the largest companies in the world,
including Facebook, Google, Adobe, Forbes, eBay, and many more. MongoDB supports field, range queries, regular expression searches. Queries can return
MongoDB is a powerful, flexible, and scalable data store. It combines the ability to scale out with many of the most useful features of relational databases, such as secondary indexes, range queries, and sorting. MongoDB is also incredibly featureful: it has tons of useful features such as built-in support for MapReduce-style aggregation and geospatial indexes. MongoDB has a developer-friendly data model, administrator-friendly configuration options, and natural-feeling language APIs presented by drivers and the database shell. MongoDB tries to get out of your way, letting you program instead of worrying about storing data.
Database is a physical compartment for accumulations. Every database gets its own set of documents on the record framework. A solitary MongoDB server commonly has numerous databases.
Collections are a gathering of MongoDB archives. It is what might as well be called a RDBMS table. An accumulation exists inside a solitary database. Accumulations don't uphold a diagram. Reports inside a gathering can have distinctive fields. Ordinarily, all reports in an accumulation are of comparable or related reason.
A document is a situated of key-quality sets. Archives have dynamic schema. Dynamic schema implies that records in the same gathering don't have to have the same set of fields or structure, and regular fields in an accumulation's archives may hold diverse sorts of data.
What is the use of MongoDB
MongoDB is relational database management system (RDBMS) replacement for web applications. So, when you have something which is close to RDBMS, MongoDB could be of good use. It gives you that additional partition tolerance which RDMBS doesn't give but it has problems with availability. But if you want more scalability, MongoDB would be your choice. It's suitable for real-time analytics and high speed logging. It's highly scalable as well. Craigslist uses MongoDB for archived posts.