Introduction to React

Before we discuss about the React library, let understand what was the need for it and what problems it solves.

Before React

Before React, dynamic web applications were built using server side UI. The whole page would reload every time the user interacted with the application, which led to a poor user experience. Or developers need to use JavaScript to manipulate the DOM directly, which could become complex and hard to maintain as the application becomes larger and has lot of code.

Then there comes the concept of Single Page Applications (SPAs).

What is a Single Page Application (SPA)?

A Single Page Application (SPA) is a web application that loads a single HTML page and when the user interacts with the app, it dynamically updates the content without reloading the entire page. This way the website becomes faster and provides a smoother user experience.

What is React?

React is a JavaScript library for building user interfaces, primarily for single-page applications. It helps developers to create large web applications that can change data without reloading the whole page. The key feature of React is the ability to build reusable UI components, which makes development more efficient and organized.

Key Features of React

React features make it a popular choice for building Single Page Applications. Some of the key features are as follows:

1. Component-Based Architecture: React applications are built using small, reusable components. Each component has its own UI and functions. By using these components, we can create complex UIs by using the smaller components together. So the code becomes easy to maintain, understand and efficient.

2. Virtual DOM: React uses a virtual DOM to update the UI efficiently. Virtual DOM is a lightweight copy of the actual DOM. When the state of an object changes, React updates the virtual DOM first, then compares it with the actual DOM and only updates the parts that have changed. This results in better performance and a smoother user experience.

3. Declarative UI: React allows developers to describe what the UI should look like for a given state, and React takes care of updating the UI when the state changes. This makes it easier to reason about the application and debug issues.

4. Unidirectional Data Flow: In React, data flows in one direction, from parent components to child components. This makes it easier to understand how data changes in the application and it helps in debugging.

5. Rich Ecosystem: React has a vast ecosystem of libraries and tools. You can use libraries like React Router for routing, Redux or Context API for state management, and many others to enhance your application.

What problem does React solve?

In earlier web development, building interactive user interfaces often involved manipulating the DOM directly, which could lead to complex and hard-to-maintain code. React simplifies this process by allowing developers to create components that manage their own state and render efficiently. This leads to a more organized codebase and a better user experience.

What other frameworks are there?

React is not the only library for building user interfaces. Other popular frameworks include:

• Vue.js: A progressive framework for building user interfaces, similar to React but with a different approach to reactivity and templating.
• Angular: A platform and framework for building single-page client applications using HTML and TypeScript. It provides a comprehensive solution with a strong opinion on application structure.
• Svelte: A relatively new framework that shifts much of the work to compile time, producing highly optimized vanilla JavaScript at the end. It offers a more straightforward and less boilerplate-heavy approach to building UIs.

Why Choose React?

React is used by many large companies and has a strong community support. It is known for its flexibility, performance, and ease of learning. If you are looking to build modern web applications with a focus on user experience, React is an excellent choice.

Next we will do the setup of the development environment and create your first React application so that you can learn by doing. Let’s get started with the Setup Guide to prepare your development environment and create your first React application.