Today under Programming course we are providing React.js course.

React (also known as React.js or ReactJS) is a free and open-source front-end JavaScript library[3] for building user interfaces or UI components. It is maintained by Facebook and a community of individual developers and companies.[4][5][6] React can be used as a base in the development of single-page or mobile applications. However, React is only concerned with state management and rendering that state to the DOM, so creating React applications usually requires the use of additional libraries for routing, as well as certain client-side functionality.[7]

The following is a rudimentary example of React usage in HTML with JSX and JavaScript.

<div id="myReactApp"></div>

<script type="text/babel">

function Greeter(props) {

return <h1>{props.greeting}</h1>;

}

let App = <Greeter greeting="Hello World!" />;

ReactDOM.render(App, document.getElementById('myReactApp'));

</script>

The Greeter function is a React component that accepts a property greeting. The variable App is an instance of the Greeter component where the greeting property is set to ‘Hello World!’. The ReactDOM.render method then renders our Greeter component inside the DOM element with id myReactApp.

When displayed in a web browser the result will be

<div id="myReactApp">

<h1>Hello World!</h1>

</div>