JavaScript and It’s use cases

Megha Chhabria
6 min readJun 24, 2021


What is JavaScript?

JavaScript is a cross-platform, object-oriented scripting language used to make webpages interactive (e.g., having complex animations, clickable buttons, popup menus, etc.). There are also more advanced server side versions of JavaScript such as Node.js, which allow you to add more functionality to a website than downloading files. Inside a host environment (for example, a web browser), JavaScript can be connected to the objects of its environment to provide programmatic control over them.

How does JavaScript work?

JavaScript is what is known as a client-side script. Most Web applications, such as Search Engine, work because of an interaction between the user’s device (e.g. computer, phone or tablet) and a remote server. The software on the remote server sends information to the client (i.e. the user’s machine) and the software on the client side reads the information and renders a Web page on screen.

Some of the dynamic website enhancements performed by JavaScript are:

  • Autocomplete
  • Loading new content or data onto the page without reloading the page
  • Rollover effects and dropdown menus
  • Animating page elements such as fading, resizing or relocating
  • Playing audio and video
  • Validating input from Web forms
  • Repairing browser compatibility issues

JavaScript Features

JavaScript is one of the most popular languages which includes numerous features when it comes to web development. It’s amongst the top programming languages as per Github and we must know the features of JavaScript properly to understand what it is capable of.

Some of the features are lightweight, dynamic, functional and interpreted. Now we are going to discuss some important features of JavaScript.

  • Light Weight Scripting language
  • Dynamic Typing
  • Object-oriented programming support
  • Functional Style
  • Platform Independent
  • Prototype-based
  • Interpreted Language
  • Async Processing
  • Client-Side Validation
  • More control in the browser

Uses and applications of JavaScript

An HTML page is a static one and without JavaScript it would be static still. JavaScript can make the website more interactive and user- friendliness of JavaScript helps easy navigation of the website and helps designers to guide the visitors with additional information or guide them through walkthroughs. Visual effects can also be achieved with JavaScript. JavaScript can be used effectively to create special effects like rollover for images.

JavaScript not only supports web pages but also supports external applications like PDF documents, running widgets, supporting for flash applications etc. JavaScript has emerged in web industry like a boom and if you look at the current web scenario there are no web technologies that are not using JavaScript.

JavaScript stands unique as it brings out all the special functionalities in the client’s browser instead of the site’s server. The role of JavaScript can never be denied as JavaScript can act as both object oriented programming and procedural language.

The future of JavaScript

While JavaScript is not the only client-side scripting language on the Internet, it was one of the first and it is still the most widely used. Many developers believe that JavaScript is inefficient and finicky, so they have made many improvements to the language over the years. Enterprising programmers have created JavaScript libraries — more concise languages constructed from the building blocks of JavaScript that are less complex and can be targeted for specific applications.

JavaScript has become integral to the Internet experience as developers build increased interaction and complexity into their applications. Search engines, ecommerce, content management systems, responsive design, social media and phone apps would not be possible without it.

What Is Node.js?

Node.js is a runtime environment that executes JavaScript code outside a browser. It is an open-source, asynchronous, back-end, and cross-platform compatible runtime environment. It is designed to build scalable apps and allows developers to use JavaScript for server-side scripting.

It is chosen by well-known brands and a wide number of enterprises that want to utilize it for better scalability and performance.

Node.js Advantages

  • Scalability:

It is one of the key advantages of Node.js. It is designed in a way that makes scalability a breeze. There are web and mobile applications that have thousands of concurrent users at a time. Node.js ensures smooth performance and greater reliability, making it a widely-popular and desirable choice for developers and large enterprises.

  • Ease to Use:

It is open-source and easy to use. As JavaScript is primarily used for server-side programming, it makes development faster and efficient. There is no need to switch between client-side and server-side programming languages.

  • Fast:

Node.js is influenced by systems like Ruby and Python. It is an asynchronous event-driven JavaScript runtime where many connections can be handled simultaneously. The architecture of Node.js free developers from worries of dead-lock and blocks. This results in easy and non-blocking I/O processes, making it easier to build scalable systems.

Companies Using Node.js

  • Uber :

Uber has popularized the ‘on-demand-economy’ model where quick accessibility is given prime importance. Uber is a prominent example of a sharing economy and after a huge success of this model, companies started uberization where mobile apps work as a mediator between service providers and clients. Uber has simplified transportation for every person and now offering more than just an on-demand taxi service. It offers services like vehicles for hire, food delivery, freight, couriers, package delivery, and vehicle rental services.

With over 110 million monthly active users worldwide, Uber is one of the largest providers in the gig economy. It carries out operations in over 900 cities worldwide.

Uber uses Node.js in its APIs, UberEats application, and almost much of its code written in Python, Node.js, Go, and Java. Uber’s API Gateway was one of the largest Node.js applications at Uber.

  • Netflix:

Hardly, there is a person who doesn’t know this name. Netflix is one of the amazingly popular over-the-top (OTT) platforms headquartered in California.

As of October 2020. Netflix had over 195 million paid subscriptions worldwide. It is one of the largest entertainment/media companies by market capitalization.

Netflix uses Node.js to handle high-volume streaming for millions of users. Architecture at Netflix is designed in a way that offers observability, debuggability, and availability. It is flexible, fast, and offers smooth performance — these are the key attractions of choosing Node.js at Netflix.

  • NASA:

NASA is an independent agency of the US federal government and dedicated to aeronautics and space research programs. NASA picked Node.js to build API-driven Node.js enterprise architecture to move spacesuits related data to a cloud database. They have also created the microservice architecture along with the goal of moving legacy apps to the modern environment. This resulted in faster data accessibility and this is how Node.js is used to break down the data barriers for the world’s leading space agency.

  • Amazon Web Services:

It is a subsidiary of Amazon and a widely-used on-demand cloud computing platform and APIs to companies, government bodies, and individuals on a pay-as-you-go basis. It has made it very easier to access on-demand servers and services. It equips everyone with the ability to build quickly and cheaply.

AWS uses many tech stacks and there are many languages and tools but Amazon majorly uses Java and JavaScript.





Megha Chhabria