What is MERN Stack

What is MERN Stack

MERN stands for MongoDB, ExpressJS, React, and Node. MERN is a Web development stack for building full stack Web applications. This means that you can build a complete Web application, including the frontend, backend, and the business logic with a database using the MERN stack.
MERN comprises of four technologies, MongoDB, ExpressJS, React, and Node. The following diagram explains the role of each technology in the MERN stack.
MERN Stack 


React, formerly known as Reactjs or React.js was originally developed by Facebook in 2011. Today, React is the most popular open-source JavaScript framework used to build Web user interfaces. React also allows us to create reusable UI components.
React allows developers to create large web applications that can change data without reloading the page. The main purpose of React is to be fast, scalable, and simple. It works only on user interfaces in the application. This corresponds to the view in the MVC template. It can be used with a combination of other JavaScript libraries or frameworks, such as Angular JS in MVC. 


ExpressJS is the middleware and sits between React and Node as a part of the MERN stack. ExpressJS is a NodeJS framework for creating server-side applications. ExpressJS provides many shorthand methods for writing the functionality provided by NodeJS.


Node or Node.js is an open-source, cross-platform JavaScript based server-side runtime framework. Unlike JavaScript, Node runs on a server. Node has recently become one of the more popular frameworks used to build Web applications based on JavaScript.
Here is a complete step-by-step tutorial series on Building Web Applications using Node.jshttps://www.c-sharpcorner.com/article/building-web-application-using-node-js/


MongoDB is a document-based, open-source database. It is also a leading NoSQL database. It provides high performance, high availability, auto-sharding and automatic scaling. MongoDB database is written mainly in C++ . It's drivers and client libraries are typically written in their respective languages, although some drivers use C extensions for better performance. MongoDB differs from relational databases because it is a schema-less database. These types of databases usually have lower transaction safety, but are faster than relational databases when it comes to accessing data and scale.
MongoDB stores data as documents. Therefore, it is a document-based database. A document is a data structure that stores the data in field and value pairs. The format of MongoDB documents is similar to JavaScript Object Notation (JSON). The values of a field may include a simple value, array and other documents. MongoDB uses BSON format to store the data into a document.

MERN Video Tutorial

Here is a full, 2-hour tutorial on MERN stack. This tutorial includes an introduction to MERN, database concepts, getting started with MongoDB Atlas, creating a backend of the exercise tracker app, an introduction to React, creating front end with React, and connecting the frontend of the application with the backend in order to complete the app.

Learn MERN

Here are detailed tutorials and learning material on MERN stack.