Destructuring and spread

What this means

Destructuring pulls values out of arrays or objects. Spread copies values into a new array or object. React examples use both constantly.

In beginner terms, this topic answers one practical question: "What should I write, and why does React care about it?" Do not try to memorize the syntax first. First understand the idea, then connect the syntax to that idea.

Why it matters

Props, state arrays, and state objects are easier to work with when you understand destructuring and spread. These features also help you avoid mutating old state directly.

When you build real React screens, this idea helps you decide where data should live, what the user should see, and what should happen after an interaction. That is why this lesson is part of the main path instead of being an optional detail.

Step by step

1. Notice the UI problem this topic solves. 2. Look at the smallest possible example. 3. Change one value and predict what should appear. 4. Run the example and compare the result with your prediction. 5. Use the practice task before moving on.

Small example

const { title } = props;
const nextItems = [...items, "React"];

Common mistake

Do not mutate state objects or arrays directly. Create a new copy with spread, then change the copy.

Practice task

Use destructuring to read a title prop, then use spread to add one item to a list.

Remember this

Destructuring reads; spread copies.