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What is key in react?

If you've ever worked with lists in React, you might have come across a special attribute called "key". But what exactly is it, and why does it matter?

In simple terms, a key is like a unique ID for each element in a list.

It helps React keep track of items, making your app faster and more efficient.

Why Keys Matter:​

  1. Efficient Updates:

When React renders a list of items, it needs a way to identify each one. Keys provide this identification, allowing React to update only the items that have changed, rather than re-rendering the entire list.

  1. Stable Reordering:

Keys ensure that React can maintain the correct order of items, even if they are rearranged.

This stability is crucial for preserving component states and avoiding unexpected behavior.

How to Use Keys:​

const myList = () => {
  const items = ['apple', 'banana', 'orange'];

  return (
    <ul>
      {items.map((item, index) => (
        <li key={index}>{item}</li>
      ))}
    </ul>
  );
};