React Jsx — Free React Tutorial
Learn React Jsx in React with a free, beginner-friendly tutorial, examples and practice for Indian students on Syllab.in.
TL;DR: Learn React Jsx in React with a free, beginner-friendly tutorial, examples and practice for Indian students on Syllab.in.
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React Jsx in React
React is a JavaScript library for building user interfaces using reusable components. Instead of writing raw HTML and JavaScript, React lets you describe what the UI should look like using a special syntax called JSX. JSX looks like HTML but runs inside JavaScript — it gets compiled into regular JavaScript function calls that create UI elements. React automatically manages updates to the DOM, only re-rendering parts that changed, which makes applications fast and responsive.
JSX combines HTML and JavaScript in a way that feels natural to developers. When you write `<div>Hello</div>` in JSX, React converts it to a function call like `React.createElement("div", null, "Hello")`. This means you can embed JavaScript expressions inside JSX by wrapping them in curly braces: `<h1>Hello, {name}!</h1>`. JSX must return a single root element, and any component name must start with a capital letter to distinguish it from regular HTML tags.
React works by creating a virtual representation of the UI in memory and efficiently syncing it with the real DOM. When state or props change, React re-renders the component, compares the new virtual DOM with the old one, and applies only the necessary changes to the actual DOM. This "reconciliation" process is what makes React fast even with complex interfaces. Understanding this mental model is key to writing React code that performs well and behaves predictably.
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