React is a JavaScript library for building user interfaces — it helps developers create fast, interactive, and modular web apps, using components as building blocks.
The library was created by Facebook (now Meta) in 2013 to solve a common headache: how to update the UI efficiently when data changes. React introduced the virtual DOM, a lightweight copy of the browser’s DOM that lets the app update only what’s necessary, rather than reloading the entire page. That means smoother performance and a better user experience.
React is all about components — reusable pieces of code that manage their own structure, style, and logic. Think of a “Like” button, a product card, or a navigation bar — in React, each is a self-contained component that can be reused, customized, or combined with others to build full apps.
Though it’s “just a library” (not a full framework), React is powerful, especially when paired with tools like React Router or state managers like Redux. It’s used by companies like Instagram, Airbnb, and Netflix — and by countless developers building everything from portfolios to complex platforms.
Want to learn it hands-on? Try React’s official tutorial.
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