React Lists:

In React, you will render lists with some type of loop.The JavaScript map() array method is generally the preferred method.

Example:

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

function Garage() {
  const cars = ['Ford', 'BMW', 'Audi'];
  return (
    <>
      <h1>Who lives in my garage?</h1>
      <ul>
        {cars.map((car) => <Car brand={car} />)}
      </ul>
    </>
  );
}

Keys:

Keys allow React to keep track of elements. This way, if an item is updated or removed, only that item will be re-rendered instead of the entire list.

Keys need to be unique to each sibling. But they can be duplicated globally.

Generally, the key should be a unique ID assigned to each item. As a last resort, you can use the array index as a key.

Example:-

JavaScript
function Bikes() {
  const model = [
    {id: 1, brand: 'Ford'},
    {id: 2, brand: 'BMW'},
    {id: 3, brand: 'Audi'}
  ];
  return (
    <>
      <h1>Who lives in my garage?</h1>
      <ul>
        {model.map((bike) => <Car key={bike.id} brand={bike.brand} />)}
      </ul>
    </>
  );
}

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