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Last Updated: Sep 14, 2023

Introduction to Node.js


Node.js is a free and open-source platform for running JavaScript applications, which is used to create networking and server-side applications.

In this blog, we’ll be learning about what is Node.js, its history, needs,  different versions, modules, advantages and disadvantages, limitations, and many more.

Introduction to Node.js

What is Node.js?

Node.js is a free, cross-platform, open-source, server-side runtime environment built on JavaScript and a library for running web applications outside the client's browser. Dahl developed Node.js in 2009; its latest version was released in 2021. Node.js platform is used by developers to create web applications. Node.js help to build complex applications quickly and easily. 

What is Node.js?

History of Node.js

We learn what is Node.js. Now let’s learn about the History of Node.js:

Ryan Dahl created Node.js. Due to the limitations of web server environments, Dahl created a platform that handles real-time, data-intensive applications. Initially, Dahl created Node.js with event-driven I/O for other programming languages. The first version has the core features, like the event loop, non-blocking I/O, and support for modules. Node.js became popular among front-end developers very quickly. It can handle large amounts of data. It became famous for building real-time applications like chat apps and online gaming platforms. In 2010, after Dahl’s presentation many high profile companies adopted Node.js like LinkedIn and Walmart.

Why Do We Use NodeJs?

Node.js is commonly used in web development to use JavaScript for server-side programming. It unifies the client and server codebases, enhancing the development experience. It also allows developers to take advantage of the extensive npm package ecosystem and cross-platform compatibility. It also has a non-blocking, asynchronous architecture, which makes it particularly useful for applications that require handling multiple concurrent connections and I/O-bound operations.

Features of Node.js

Let’s understand some of the Features of Node.js which includes:

  1. Single-threaded: Node.js platform does not follow the Multi-Threaded Model. It only follows the Single Threaded ModelSingle threaded means that only one request at a time Node.js can handle.
  2. Common language: Due to common language characteristics of Node.js, developers can use the same language for both front-end and back-end development which help in reducing development time. JavaScript is the primary language of Node.js.
  3. Modular architecture: Node.js has a modular architecture and It has small, reusable modules. Due the modular architecture of Node.js it helps to simplify the development and also improves the code quality.
  4. Lightweight: Node.js is very lightweight. It has a small footprint which makes  it ideal for running on servers with limited resources.
  5. Cross-platform: Due to this characteristics of Node.js it can run on any platform like Windows, Linux, and macOS because of this  it is easy in Node.js to create applications that can run on different platforms without any changes.

Node.js Architecture

The architecture of Node.js is designed for asynchronous and event-driven programming. Its core components are:-

  • V8 Engine: At the core of Node.js is the V8 JavaScript engine which is developed by Google. It compiles JavaScript code to machine code, which makes the JavaScript execution extremely fast.
  • Event Loop: Node.js works on an event loop, which is an important part of its architecture. The event loop continuously checks for events, such as incoming HTTP requests, file system operations, or timers, and processes them in a non-blocking manner. This allows Node.js to efficiently handle many concurrent operations without waiting for each one to complete.
  • Libuv: Libuv is a multi-platform library that provides the event loop implementation for Node.js, which handles I/O operations and abstracts their differences between various operating systems making Node.js platform independent.
  • Modules: Node.js uses the module system that allows developers to organize their code into reusable modules.

Different Version of Node.js

So far we learn what is Node.js, Its history, characteristics. Now let’s learn about different versions of Node.js:

Some of the different versions of Node.js are the following:


  1. Node.js 0.10.x: In March 2013,Node.js 0.10.x was released.The very first stable version of Node.js. This version includes the Streams2 API
  2. Node.js 0.12.x: Node.js 0.12.x was released in February 2015. This version improves the V8 engine and supports ECMAScript 6 (ES6) features.
  3. Node.js 4. x: Node.js 4. x was released in September 2015. This version of Node.js has a Long-Term Support (LTS) release line.
  4. Node.js 6. x: Node.js 6. x was released in April 2016. This version improves on the V8 engine. Enhance the support for ES6 features and improve HTTP performance in this new version of Node.js.
  5. Node.js 8. x: Node.js 8. x was released in May 2017. This version improves the core APIs and adds some new features in Node.js, like async/await syntax for asynchronous code.
  6. Node.js 10. x: Node.js 10. x was released in April 2018. This version came with better support for HTTP/2.
  7. Node.js 12. x: Node.js 12. x was released in April 2019. This version improves performance, enhances the capabilities of debugging, and comes with better support for ES6 modules.
  8. Node.js 14. x: Node.js 14. x was released in April 2020. This version improves on the event loop and garbage collection. Enhancement in diagnostics capabilities and better support for ECMAScript features.
  9. Node.js 16. x: Node.js 16. x was released in April 2021. This version improves the V8 engine and better supports ECMAScript features. In this version, it also supports for Apple Silicon

Need of learning Node.js

Node.js are very beneficial for developers. Let’s learn some of the key reasons why to learn Node.js:

  1. Large and active community: No doubt Node.js has a large community of developers. There are ample resources available for learning and development purposes like tools, and libraries. 
  2. Server-side development: For Server-side development, developers used Node.js. The term “Server-side development” means that it is used to build web servers and RESTful APIs. If we learn Node.js, it can help us to create efficient and scalable applications.
  3. Integration with front-end technologies: With front-end technologies like React, Vue.js, and Angular, Node.js can integrate. By using Cors Module, Developers can create a full stack application.
  4. Asynchronous programming: Asynchronous programming can handle a large number of requests without blocking the event loop. It also improves application performance and scalability.
  5. Cross-platform development: Node.js is cross-platform, which can be used to develop applications on different platforms like Windows, Linux, and macOS. This will help developers create applications that can run on multiple platforms easily.

Environment Setup of Node.js

The prerequisite for setting up the Node.js environment is that we own a PC with Windows installed on it. Let’s get started with the Environment setup.

Installation and Setting up the Environment

Below are the installation steps.

1. To install Node.js. we have to visit the official website of Node.js and download it according to your operating system.

  • Accept the terms in the license agreement and click next.
  • Click on install to install the Node.js
  • Click on finish. Now, you have successfully installed Node.js.

2. Now, open windows powershell and type node –version to display the version of the node installed.


3. After successful installation of Node.js. We are all ready to use our platform. 

NOTE:  From the official Node.js website download the Windows Installer and do install the latest version (include NPM package manager) of Node.js.

REPL in Node.js

In Node.js, REPL is an abbreviation of Read-Eval-Print-Loop. It is a built-in tool. It allows developers to interactively run Node.js code.

REPL in Node.js

Components of REPL:


  1. Read REPL; Read component reads input from the user. The input can be in the form of JavaScript code, expressions, or commands.
  2. Eval: REPL, Eval component takes the input read by the Read component. It evaluates it as JavaScript code and, in output, gives a result or an error.
  3. Print: REPL, Print component prints the result of the evaluated code.
  4. Loop: REPL, Loop component repeats the Read, Eval, and Print steps. The Loop component can be exited by typing .exit.

     Some key features of the Node.js REPL are given below:

  • By typing node in the terminal or console, we can access it.
  • We can also access the history of previously entered commands.
  • It also supports tab completion. This can be used to autocomplete the commands.
  • By using the require() function, we can load modules as well as execute the modules.

Basics of Node.js

So far, we have learned a lot like what is Node.js, Its history, Different versions and many more. Now let’s learn some basics of Node.js:

  1. Data Types: Node.js supports several built-in data types like numbers, strings, booleans, null, undefined, and objects. Numbers in Node.js can be integers or floating-point, and strings can be created using single or double quotes. Booleans represent true or false values, while null represents empty values. In Node.js, objects are collections of key-value pairs which can contain any combination of data types.
  2. Loose Typing: Node.js is a platform which supports loose-typed language. Variables are not required to be declared with specific data types. Instead variable data type is determined based on the value assigned to it.
  3. Object Literal: In Node.js, object literals are a key feature. It allows developers to create and manipulate objects by using a simple syntax. Object literals use {} brackets, which define key-value pairs separated by commas.
  4. Buffer: In Node.js, For raw binary data, a temporary storage area is there in Node.js, which is called a buffer, and it is used to manipulate data. By using the Buffer from() or Buffer.alloc() methods, we can create Buffer. 
  5. Functions: In Node.js, Using the function keyword, functions can be defined easily. Anonymous functions that are used as callbacks also supported in Node.js

Module in Node.js

In Node.js, modules are self-contained units of code. Modules can easily reused and imported into other applications. It contains functions, classes, and objects. They can also have dependencies on other modules.

Here are three types of modules in Node.js given below:

Module in Node.js

1. Core Modules:

Core modules are built-in modules. These modules provide us with essential functionalities which help in building Node.js applications. HTTP, fs, path, and so are examples of core modules in Node.js

2. Local Modules:

Local modules are created by developers and stored in separate files or directories within the application. These modules are used to encapsulate functionality and improve code organization. Local modules can easily be imported and used within the same application by using the require() function.

3. Third-Party Modules:

Third-party modules are created by developers outside of the application. It can be installed by using Node Package Manager (NPM). These modules are published to the NPM registry. Modules can be easily installed using the npm install command. Third-party modules can provide functionality, from database connectors and utility libraries to complete frameworks and plugins. Express, Socket.IO, and Mongoose are examples of third-party modules.

Node Package Manager 

NPM is an abbreviation for Node Package Manager. NPM is a command-line tool. It is used to install, manage, and share packages or modules of JavaScript code. NPM is the largest package repository, with millions of packages used in Node.js applications. 

Let’s learn commands to install, uninstall, and update packages using npm:

Install a package: 

For installing packages, we have to use the npm install command followed by the name of the package. Let’s understand this by taking an example: Say we have to install an express package, then the following command is used:

npm install express 

By using the above command, we can install the express package along with its dependencies in the node_modules directory.

Uninstall a package:

For the uninstallation, we can use the npm uninstall command followed by the name of the package. Let’s understand this by taking an example: Say we have to uninstall the package, then the following command is used:

npm uninstall express

By using the above command, we can remove the express package along with its dependencies in the node_modules directory.

Update a package:

For the updation purpose, we can use the npm update command followed by the name of the package. Let’s understand this by taking an example: Say we have to update the package, then the following command is used:

npm update express express     


Using the above command, we can update the express package to the latest version and install any new dependencies.

The above install, uninstall and update commands only affect the packages installed in the current project. If we want to install, uninstall and update packages globally, we must add the -g flag. Let’s understand this command by the following example:

npm install -g express

Applications of Node.JS

Some of the most common applications of Node.js are given below:

  1. Chat applications: Node.js is used to build chat applications, as it can handle real-time communication and high concurrency. Its architecture allows it to handle multiple chats simultaneously, with high performance.
  2. Desktop applications: In Node.js, developers can create desktop applications including electron based applications. Node.js allows developers to build cross platform applications.
  3. Web applications: Node.js is also used to build web applications like social networking, e-commerce and real time applications. 
  4. Internet of Things devices: Node.js offers a platform where we can build IoT devices like sensors and controllers. It runs on low-power devices, and its support for hardware interfaces.
  5. Streaming applications: Node.js is used to build applications like video streaming platforms and music streaming services. It allows for handling large data streams efficiently.

Advantages of using Node.JS

 Some of the advantages of using Node.js are given below:

  1. High performance: Node.js is known for its high performance. It handles many concurrent connections using a less resources.
  2. Flexibility: Node.js offers flexibility to use both server-side and client-side development. It can build web and desktop applications, Internet of Things devices, and command-line tools. 
  3. Easy to learn: Frontend developers are familiar with JavaScript. It will easier for developers to get started using Node.js on the backend. It is easy to understand Node.js, and working with it takes less time.
  4. Cross-platform compatibility: Node.js is available on multiple platforms, which allows developers to build applications that can run on multiple platforms.
  5. Powerful Data Processing: Node.js is a perfect platform for efficient data-handling tools. Most of the backend development platforms use synchronous processing but Node.js adopt asynchronous structure for upcoming requests to process together with the first one. 

Limitations of using Node.JS

Some of the limitations of using Node.js are given below:

  1. Limited Multi-threading capabilities: Due to the single threaded architecture of Node.js, it is not much suitable for CPU intensive tasks as CPU intensive tasks require multi threading.
  2. Security vulnerabilities: Apart from all the advantages, Node.js has a limitation in terms of security. Node.js has security vulnerabilities. Some practices can reduce the risk of security breaches like input validation, encryption and secure coding techniques.
  3. Performance issues with large-scale applications: Apart from the fact that Node.js has a high performance but still it struggles with large scale applications. As these applications with large scale require high memory usage too.
  4. Lack of built-in support for relational databases: SQL databases are not supported by Node.js. However, modules in Node.js can handle interfaces with SQL databases.
  5. Complexity of asynchronous programming: Node.js use asynchronous programming. This programming makes the code writing, debugging and maintenance more challenging.

Disadvantages of using Node.JS

Let’s learn Some of the disadvantages of Node.js:

  1. Single-threaded: The main disadvantage of Node.js is that it is  single-threaded which means it only handles one task at a time. 
  2. Libraries:  In Node.js, it has many packages. Although it lacks in libraries and tools for machine learning or data analysis. 
  3. Debugging: Node.js applications debugging can be challenging. Developers should be familiar with debugging tools and techniques. Specifically, Node.js to troubleshoot issues.
  4. Security: Node.js has security vulnerabilities. So attackers can exploit them. To ensure the security of the application, developers should use authentication and authorization mechanisms.
  5. Limited applications support: In Node.js, it does not support CPU-intensive applications however it supports I/O-bound applications.

Also Read, Front End Web Development

Frequently Asked Questions

What is Node.js used for?

Node.js is used to create server-side web applications and it is the best platform for data-intensive applications. 

Is Node.js a programming language?

No, Node.js is not a programming language. It is a JavaScript runtime environment, open source, cross-platform.  

Is Node.js a framework?

No, Node.js is not a framework. It's a JavaScript runtime environment.

Is Node.js backend or frontend?

Node.js is mainly used for backend development. JavaScript is used only for frontends.

What is difference between NodeJS and ReactJS?

Node.js is a server-side runtime environment for JavaScript commonly used to build backend applications, while ReactJS is a frontend JavaScript library used for building client-side web applications. These technologies are commonly used together for building full-stack applications.


We hope this article helped you understand what is Node.js, Node.js framework and other basic concepts. You will find straightforward explanations of almost every topic on our platform. You can read more such articles on our platform, Coding Ninjas Studio. So take your learning to the next level using Coding Ninjas. 

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