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## Introduction to MongoDB 

Welcome to MongoDB. This document provides a brief introduction to MongoDB and some key concepts. See the installation guides (page 5) for information on downloading and installing MongoDB. 

## 1.1 What is MongoDB 

MongoDB is an open-source document database that provides high performance, high availability, and automatic scaling. 

## 1.1.1 Document Database 

A record in MongoDB is a document, which is a data structure composed of field and value pairs. MongoDB docu- ments are similar to JSON objects. The values of fields may include other documents, arrays, and arrays of documents. 

<img src='content_image/746214.jpg'>

The advantages of using documents are: 

• Documents (i.e. objects) correspond to native data types in many programming languages. 

• Embedded documents and arrays reduce need for expensive joins. 

• Dynamic schema supports fluent polymorphism. 

