1. What is JSX?

JSX (JavaScript XML) is a syntax extension for JavaScript that allows you to write HTML-like code inside your JavaScript files. It makes building user interfaces with React more intuitive and readable.

• Combines JavaScript and HTML: JSX lets you write HTML structures directly in JavaScript files.
• Not a Template Language: Unlike templating engines, JSX allows you to write JavaScript expressions within HTML tags.
• Transpiled: JSX is transpiled into regular JavaScript using tools like Babel before it runs in the browser.

2. JSX Syntax

JSX is similar to HTML but has some key differences:

• Use className instead of class to define CSS classes.
• All JSX elements must have a closing tag (e.g., <br />).
• JavaScript expressions are enclosed in curly braces {}.

Example:

function Greeting() {
    const name = "John";
    return (
        

            
Hello, {name}!
        
    );
}
                

Explanation: The Greeting component uses JSX to dynamically display the value of the name variable.

3. Embedding Expressions in JSX

JSX allows you to embed JavaScript expressions inside curly braces:

function TimeDisplay() {
    const currentTime = new Date().toLocaleTimeString();
    return (
        

            
The current time is: {currentTime}
        
    );
}
                

In this example, the current time is dynamically displayed in the JSX structure.

4. JSX with Conditional Rendering

You can use JavaScript logic inside JSX for conditional rendering:

function UserStatus({ isLoggedIn }) {
    return (
        

            {isLoggedIn ? 
Welcome back!
 : 
Please log in.
}
        
    );
}
                

Explanation: The UserStatus component renders different messages based on the isLoggedIn prop.

5. Advantages of JSX

• Improved Readability: JSX simplifies combining HTML and JavaScript logic.
• Prevents Injection Attacks: JSX automatically escapes any values embedded in the HTML.
• Integration with React: JSX works seamlessly with React’s component model.