Difference between Framework and Library

Framework Vs Library

React is a JavaScript library, not a framework. It is primarily used for building user interfaces (UI), especially single-page applications (SPAs).

1. What is a library?

A library is a collection of reusable functions and tools that developers can call whenever needed.

• You control the application flow.

• You decide when and where to use the library.

• It generally solves a specific problem.

Examples:

• React – Building user interfaces.

• jQuery – DOM manipulation and AJAX.

• Lodash – Utility functions.

• Axios – Making HTTP requests.

2. What is a framework?

A framework provides a structured foundation for developing an application.

• It defines the application's structure and flow.

• It provides predefined conventions and features.

• The framework often controls when your code gets executed. This is called Inversion of Control.

Examples:

• Angular – Frontend application development.

• ASP.NET Core – Backend and web application development.

• Django – Python web application development.

• Spring Boot – Java application development.

3. Library vs Framework

4. Why is React a library?

Consider a React application:

import React from 'react';

function App() {
    return (
        <div>
            <h1>Hello React</h1>
        </div>
    );
}

export default App;

React provides components and tools to build the UI.

However, React itself does not prescribe a complete application architecture. For additional functionality, you choose other libraries:

This flexibility is one reason React is classified as a library.

Important interview point:

React is a JavaScript library because it primarily focuses on building the UI layer. Developers can choose additional libraries and tools for routing, state management, HTTP communication, and other application requirements.

Note: Angular is generally classified as a framework because it provides a more integrated application development structure and toolset.