MEAN Stack vs MERN Stack

A well-liked JavaScript-based technological stack for creating dynamic web applications is called the MERN stack. The MERN full form is MongoDB, Express.js, React.js, and Node.js. It is made up of four tech stack elements:

• MongoDB: A NoSQL database called MongoDB keeps data in an adaptable format like JSON. It is well-known for being scalable, performant, and user-friendly, which makes it ideal for managing massive amounts of data in online applications.
• Express.js: A simple web application framework based on Node.js is Express.js. It offers a comprehensive feature set, including template engines, middleware support, and routing, for developing web servers and APIs. Writing backend code and managing HTTP requests and answers is made easier using Express.js.
• React.js: React is a powerful JavaScript library for building user interfaces. It lets developers quickly manage the state of their projects and construct reusable user interface components. Web applications run more smoothly and are easier to maintain because of their component-based design and virtual DOM implementation. 
• Node.js: Node.js is a server-side JavaScript runtime environment. By enabling the execution of JavaScript code outside of a browser, MERN stack developers may use the same language and environment to create front-end and back-end services and APIs. Because Node.js offers event-driven, non-blocking I/O, it may be used to create high-performance, scalable web servers.

Thus, MongoDB, Express.js, React.js, and Node.js form the MERN stack, offering a comprehensive solution for developing modern web applications.

The MEAN stack is also a JavaScript tech stack used for building dynamic web applications. It consists of four main elements:

• MongoDB: As mentioned above, MongoDB is a NoSQL database that stores data in a flexible, JSON-like format. 
• Express.js: Express.js provides a robust set of features for building web servers and APIs, including routing, middleware support, and template engines. Express.js simplifies the process of creating backend logic and handling HTTP requests and responses.
• Angular.js: Angular is a powerful JavaScript framework for building dynamic single-page web applications (SPAs). Developed by Google, Angular offers a comprehensive set of features for building complex user interfaces, including data binding, dependency injection, and modular architecture. It provides developers with tools for creating responsive, interactive web applications with a focus on maintainability and scalability.
• Node.js: Node.js is built on the V8 JavaScript engine. It allows developers to run JavaScript code outside the browser, enabling them to build backend services and APIs using the same language and ecosystem as the front end. 

Thus, utilizing React.js and Angular.js in the MERN stack and MEAN stack is the sole distinction between them.

Below is how the MERN stack works:

• Frontend with React: In MERN, React is used to create the front end of the web application. To build reusable components, developers use React to manage the application’s state efficiently. React utilizes a virtual DOM for rendering UI components, which helps improve performance by minimizing DOM manipulation.
• Backend with Node.js and Express.js: In the MERN, Node.js and Express.js are used together to build the backend of the application. Developers use Express.js to define routes, handle HTTP requests and responses, and implement business logic on the server side. Node.js provides the runtime environment for executing JavaScript code on the server, allowing developers to use JavaScript for both frontend and backend development.
• Data Storage with MongoDB: In the MERN stack, MongoDB is used as the database to store and manage application data. Developers can easily store and retrieve data from MongoDB using JavaScript, making it seamless to work with data across the entire stack.
• Integration: The front end and back end of the MERN application are integrated using HTTP requests. When a user interacts with the front end of the application (built with React), the front end sends HTTP requests to the backend server (built with Node.js and Express.js). The backend server then processes these requests, interacts with the MongoDB database as needed, and returns the appropriate response to the frontend. 

Below is how the MEAN stack operates:

• Frontend using Angular: The application’s user interface is made with Angular in the MEAN stack. Angular’s data binding, modular architecture and dependency injection capabilities let developers construct reusable components and effectively manage the state of the application.
• Backend built with Node.js and Express.js: The backend is constructed using a combination of Node.js and Express.js. Express.js is used by developers to manage HTTP requests and replies, build routes, and implement server-side business logic. JavaScript may be used for both frontend and backend development as Node.js offers the runtime environment needed to run JavaScript code on a server.
• Data Storage with MongoDB: MongoDB serves as the database for managing and storing application data in the MEAN stack. JavaScript makes it simple for developers to save and retrieve data using MongoDB, facilitating smooth data manipulation throughout the whole stack. 
• Integration: HTTP requests are used to integrate the MEAN stack application’s front end and back end. The application’s frontend, which is created using Angular, communicates with the backend server, which is created with Node.js and Express.js, over HTTP requests. Following that, the backend server handles these requests and communicates with the MongoDB.