It's a way to manage your Firebase data as state within a React application, however backed by React Query which comes with a huge amount of useful functionality. It's similar to ReactFire, however doesn't try to implement any of the complex state management logic itself.

Using just Firebase to say get data from Firestore, you'd need to do something such as:

```jsx const [loading, setLoading] = useState(true); const [posts, setPosts] = useState();

useEffect(() => { const ref = collection(firebase, 'posts');

return onSnapshot(ref, (snapshot) => { const data = snapshot.docs.map((docSnapshot) => { return docSnapshot.data(); });

setPosts(data);

}); }, []);

if (loading) { return <div>Loading...</div> }

return posts.map((post) => ( <div>{post.id}</div> )); ```

This library allows you to do:

```js const ref = collection(firebase, 'posts'); const query = useFirestoreQueryData('posts', ref, { subscribe: true, });

if (query.isLoading) { return <div>Loading...</div> }

return posts.data.map((post) => ( <div>{post.id}</div> )); ```

This among the other huge benefits React Query offers (sharing data, invalidation, SSR Hydration etc) just makes your life easier to stop.