# class vs className In HTML, it’s common to use class as an attribute name: <h1 class="big">Hey</h1> In JSX, you can’t use the word class! You have to use className instead: <h1 className="big">Hey</h1> This is because JSX gets translated into JavaScript, and class is a reserved word in JavaScript. When JSX is rendered, JSX className attributes are automatically rendered as class attributes. # Dum class: jismain na state ho na props # example class jahan extends React.Component{ render(){ return (<h2>fghfh</h2>); } } # smart class: jismain ya to state ho ya props ho koi ek hon chahiye # example: class jahan extends React.Component{ render(){ return ( <h2>{this.props.name}</h2> ); } } or class Name extends React.Component { constructor(props) { super(props); this.state = { text: "" }; } render() { return ( <div> <p>You typed {this.state.text}</p> </div> ); } }