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# Please explain how [...planets] can be used?

I originally had the code like this and it worked. But I noticed in the final project, [...planet] was used. I don't understand how this works.

My original working code without [...planet]

const Container = (props) => { return ( <div class="container"> {props.planets.map((p) => ( <Planet url={p.url} name={p.name} desc={p.desc} moons={p.moons} diameter={p.diameter} key={p.id} /> ))} </div> ); };

The Spread Operator There are many ways you can use the spread operator.

```const numbers = [ 1, 2, 3 ]

function print( one, two, three) {
console.log(one)
console.log(two)
console.log(three)
}

print( ...numbers )
```
```function array( ...args ) {
for (let i = 0; i < args.length; i++)
console.log( args[i] )
}

array( 1, 2, 3)
```
```const array1 = [ 1, 2, 3 ]
const array2 = [4, 5, 6 ]
const array3 = [ ...array1, ...array2 ]
```
```let obj1 = { one: 1, two: 2 }
let obj2 = { three: 3, four: 4 }

let copy = { ...obj1 }
let merge = { ...obj1, ...obj2 }
```

I will need to see your whole code to help you out with this. Looks like your trying to build a HTML String.

I don't use semicolons in my JavaScript code, since they are optional.

Semicolons after statements may be technically optional, but they are most definitely a "best practice".
You might want to reconsider using them! â€ƒ