Here are some question-based titles based on your article about the `useEffect` hook: Focusing on the Core Concepts: * useEffect in React: When Should You Use It and Why? * Mastering useEffect Hook:

UseEffect Hook in Depth

When to Use useEffect?

useEffect is a React hook that allows components to perform side effects (e.g., data fetching, event handling, etc.) outside of the render phase. It takes two parameters: a callback function and an optional array of dependencies.

useEffect with No Second Parameter

<code class="javascript">useEffect(() => {});</code>

This form of useEffect runs after every render phase. It's analogous to placing the callback directly in the component body, but with a subtle difference. Typically, this form is used for debugging purposes or for defining reusable hooks.

useEffect with an Empty Second Parameter

<code class="javascript">useEffect(() => {}, []);</code>

This form of useEffect runs only on the initial mount of the component. It's often used for initializing component state or fetching data. The empty second parameter indicates that no dependencies are watched.

useEffect with Arguments in the Second Parameter

<code class="javascript">useEffect(() => {}, [arg]);</code>

This form of useEffect runs when any of the arguments in the second parameter change. It's commonly used for responding to prop or state changes. The callback runs after every render, and its cleanup function runs when the tracked dependencies change.

Additional Points to Note

• useEffect callbacks run after the browser's re-render phase.
• useEffect callbacks are executed in their declared order.
• Every useEffect should have a single, well-defined responsibility.
• When accessing the value of a ref, always copy it into the callback's scope for safety.
• useEffect is commonly used to run specific code only once, either on mount or on first render.

Further Reading

• [Explaining the Return Statement of useEffect](https://dev.to/sanggam/explaining-the-return-statement-of-useeffect-4b97)
• [Dan Abramov's A Complete Guide to useEffect](https://overreacted.io/a-complete-guide-to-useeffect/)
• [useEffect API](https://reactjs.org/docs/hooks-reference.html#useeffect)
• [Using the Effect Hook](https://reactjs.org/docs/hooks-effect.html)

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