React Development Journey Series: Understand About JSX


Welcome to the exciting world of ReactJS, where building dynamic and interactive user interfaces becomes a breeze, thanks to a powerful language extension called JSX. In this article, we'll explore what JSX is, why it's a game-changer in React development, and unravel the magic behind its seamless integration with JavaScript.

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What is JSX?

JSX, or JavaScript XML, is an extension to JavaScript that allows us to write HTML-like code directly within our JavaScript files. It's a syntax extension that React developers use to describe what the UI should look like. This makes the process of building and composing components in React more intuitive and visually similar to the final output.

const element = <h1>Lets have fun with JSX!</h1>;

Why JSX in React?

The use of JSX in React is not just a matter of preference; it significantly enhances the developer's experience. JSX simplifies the syntax for defining UI components, making it more readable and expressive. By blending HTML-like tags with JavaScript logic, JSX streamlines the process of creating and maintaining complex UI structures, making React development more approachable for JavaScript developers.

How JSX Works Under the Hood

Underneath the apparent simplicity of JSX lies a sophisticated process during compilation. JSX code is transformed into regular JavaScript functions called React elements. These elements are the building blocks of React applications, representing the structure of the UI. The React library then efficiently renders these elements to the DOM for a seamless user experience.

Key Points

For JavaScript developers making the leap to React, keep these key points in mind:

  1. JSX is Not HTML: While JSX looks similar to HTML, it's important to remember that it's not the same. JSX elements are transformed into JavaScript functions by the React, allowing for dynamic and efficient rendering.
    const name = 'Mac';
    const element = <p>Hello, {name}!</p>;
  2. Embedding JavaScript Expressions: JSX allows the embedding of JavaScript expressions within curly braces {}. This enables dynamic content rendering and the execution of logic directly within the JSX code.
    const isLoggedIn = true;
    const element = <p>{isLoggedIn ? 'Welcome back!' : 'Please log in.'}</p>;

The 'className' Attribute

One notable aspect of JSX syntax is the use of 'className' instead of 'class' for defining CSS classes. This is due to the fact that 'class' is a reserved keyword in JavaScript. So, in JSX, we use 'className' to assign CSS classes to elements, maintaining compatibility with JavaScript conventions.

const element = <div className="container">Welcome to React Development Journey Series</div>;


In conclusion, JSX is a powerful tool that simplifies React development, making it more accessible for JavaScript developers. Its seamless integration with JavaScript, intuitive syntax, and efficient rendering process contribute to the overall ease of building robust and dynamic user interfaces in React. As you embark on your React journey, keep these key points in mind, and soon you'll be crafting engaging UIs with confidence.