What is the useEffect hook in React?

Can you explain what the useEffect hook does in React?

Sure! The useEffect hook lets you perform side effects in function components, like data fetching or subscriptions.

How does it differ from componentDidMount?

Unlike componentDidMount, useEffect can run after every render, allowing you to manage updates and cleanups.

Can you give me an example of how to use it?

Absolutely! Here's a simple example: useEffect(() => { fetchData(); }, []); This fetches data only once after the component mounts.

What happens if I don't include the dependency array?

If you omit the dependency array, useEffect runs after every render, which can lead to performance issues.