Props are arguments passed into React components.

Props are passed to components via HTML attributes.

React Props

React Props are like function arguments in JavaScript and attributes in HTML.

To send props into a component, use the same syntax as HTML attributes:

const myElement = <Car brand="Ford" />;

The component receives the argument as a props object:

function Car(props) {
  return <h2>I am a { props.brand }!</h2>;
}

Pass Data

Props are also how you pass data from one component to another, as parameters.

function Car(props) {
  return <h2>I am a { props.brand }!</h2>;
}

function Garage() {
  return (
    <>
      <h1>Who lives in my garage?</h1>
      <Car brand="Ford" />
    </>
  );
}

const root = ReactDOM.createRoot(document.getElementById('root'));
root.render(<Garage />);

If you have a variable to send, and not a string as in the example above, you just put the variable name inside curly brackets:

function Car(props) {
  return <h2>I am a { props.brand }!</h2>;
}

function Garage() {
  const carName = "Ford";
  return (
    <>
      <h1>Who lives in my garage?</h1>
      <Car brand={ carName } />
    </>
  );
}

const root = ReactDOM.createRoot(document.getElementById('root'));
root.render(<Garage />);

Or if it was an object:

function Car(props) {
  return <h2>I am a { props.brand.model }!</h2>;
}

function Garage() {
  const carInfo = { name: "Ford", model: "Mustang" };
  return (
    <>
      <h1>Who lives in my garage?</h1>
      <Car brand={ carInfo } />
    </>
  );
}

const root = ReactDOM.createRoot(document.getElementById('root'));
root.render(<Garage />);

function Person(props) {
  return <h2>I'm { props.name }!</h2>;
}

function Greeting() {
  const name = "Jesse"
  return (
    <>
      <h1>Hello!</h1>
      <Person name= name  />
    </>
  );
}

const root = ReactDOM.createRoot(document.getElementById('root'));
root.render(<Greeting />);