React js

React Quiz Test your React skills with a quiz. My Learning Track your progress with the free "My Learning" program here at W3Schools. Log in to your account, and start earning points! This is an optional feature. You can study W3Schools without using My Learning. Create React App To learn and test React, you should set up a React Environment on your computer. This tutorial uses the create-react-app. The create-react-app tool is an officially supported way to create React applications. create-react-app. Open your terminal in the directory you would like to create your application. Run this command to create a React application named my-react-app: Note: If you've previously installed create-react-app globally, it is recommended that you uninstall the package to ensure npx always uses the latest version of create-react-app. To uninstall, run this command: npm uninstall -g create-react-app. Run the React Application Run this command to move to the my-react-app directory: You will learn more about the create-react-app in the What You Should Already Know Before starting with React.JS, you should have intermediate experience in: • HTML • CSS • JavaScript You should also have some experience with the new JavaScript features introduced in ECMAScript 6 (ES6), you will learn about them in the

For those who are new to web development, or trying to figure out what all the fuss is about, let’s look at React, how it works, and what makes it different from other What is React.js? The React.js framework is an open-source JavaScript framework and library developed by Facebook. It’s used for building interactive user interfaces and web applications quickly and efficiently with significantly less code than you would with vanilla JavaScript. In React, you develop your applications by creating reusable components that you can think of as independent Lego blocks. These components are individual pieces of a final interface, which, when assembled, form the application’s entire user interface. React’s primary role in an application is to handle the view layer of that application just like the V in a model-view-controller (MVC) pattern by providing the best and most efficient rendering execution. Rather than dealing with the whole user interface as a single unit, React.js encourages developers to separate these complex UIs into individual reusable components that form the building blocks of the whole UI. In doing so, the ReactJS framework combines the speed and efficiency of JavaScript with a more efficient method of manipulating the DOM to render web pages faster and create highly dynamic and responsive web applications. A Brief History of React.js Back in 2011, Facebook had a massive user base and faced a challenging task. It wanted to offer users a richer user experience by...

• Complete beginners start here! • Getting started with the web • • • • • • • • • • HTML — Structuring the web • Introduction to HTML • • • • • • • • • • • Multimedia and embedding • • • • • • • • HTML tables • • • • • CSS — Styling the web • CSS first steps • • • • • • • CSS building blocks • • • • • • • • • • • • • • • • • • • • • • Styling text • • • • • • • CSS layout • • • • • • • • • • • • • • JavaScript — Dynamic client-side scripting • JavaScript first steps • • • • • • • • • • • JavaScript building blocks • • • • • • • • • Introducing JavaScript objects • • • • • • • • • Asynchronous JavaScript • • • • • • • Client-side web APIs • • • • • • • • • Web forms — Working with user data • Core forms learning pathway • • • • • • • • • • • • Advanced forms articles • • • • Accessibility — Make the web usable by everyone • Accessibility guides • • • • • • • • • Performance — Making websites fast and responsive • Performance guides • • • • • • • • • • • • MathML — Writing mathematics with MathML • MathML first steps • • • • Tools and testing • Client-side web development tools • • • • • • • Introduction to client-side frameworks • • • React • • • • • • • • Ember • • • • • • • Vue • • • • • • • • • • Svelte • • • • • • • • • Angular • • • • • • • Git and GitHub • • Cross browser testing • • • • • • • • • • Server-side website programming • First steps • • • • • • Django web framework (Python) • • • • • • • • • • • • • • • • • Express Web Framework (node.js/JavaScript) • • • ...

React (sometimes spelled React.js or ReactJS) is one of the most popular JavaScript libraries to develop powerful, interactive web applications. You’ll learn how to start with React and build up to dynamic user interfaces. You’ll work with React specific concepts like: JSX, components, state, props, hooks, and more. Take this course to gain an edge as a front-end or full-stack web developer. Jiwon Shin Senior Curriculum Developer at Codecademy Jiwon is a Senior Curriculum Developer at Codecademy. She has created courses across the web development catalog on languages such as JavaScript, PHP, and CSS, frameworks like React and Node.js, and the Front-End Engineer Career Path. She also created courses on p5.js, build tools, and Intro to UI and UX Design. This course teaches you React from the very basics up to a really good level of understanding of the framework like no other. It's complicated to find a proper way of learning React. Video courses are fine, but there's nothing like 'getting your hands dirty' while having an interactive environment and a text guide. It makes you feel smart because you understand the topic! I loved it and I've already recommended Codecademy and their courses to people.

Stay true to the web People expect web app pages to load fast. On the server, React lets you start streaming HTML while you’re still fetching data, progressively filling in the remaining content before any JavaScript code loads. On the client, React can use standard web APIs to keep your UI responsive even in the middle of rendering. This is why React is more than a library, an architecture, or even an ecosystem. React is a community. It’s a place where you can ask for help, find opportunities, and meet new friends. You will meet both developers and designers, beginners and experts, researchers and artists, teachers and students. Our backgrounds may be very different, but React lets us all create user interfaces together.

React is a JavaScript library created by Facebook React is a User Interface (UI) library React is a tool for building UI components React Quickstart Tutorial This is a quickstart tutorial. Before you start, you should have a basic understanding of: • What is • What is • What is • What is • What is • What is For a full tutorial: Adding React to an HTML Page This quickstart tutorial will add React to a page like this: Test React // JSX Babel code goes here What is Babel? Babel is a JavaScript compiler that can translate markup or programming languages into JavaScript. With Babel, you can use the newest features of JavaScript (ES6 - ECMAScript 2015). Babel is available for different conversions. React uses Babel to convert JSX into JavaScript. const element = Hello World! As you can see above, JSX is not JavaScript nor HTML. JSX is a XML syntax extension to JavaScript that also comes with the full power of ES6 (ECMAScript 2015). Just like HTML, JSX tags can have a tag names, attributes, and children. If an attribute is wrapped in curly braces, the value is a JavaScript expression. Hello World! const name = 'John Doe'; ReactDOM.render( Hello !, document.getElementById('id01')); React Elements React applications are usually built around a single HTML element. React developers often call this the root node (root element): The examples on this page compiles JSX in the browser. For production code, the compilation should be done separately. Create React Application ...