We can iterate over arrays using the `for` loop. The syntax is:

```javascript
for (let i = 0; i < array.length; i++) {
  // do something with array[i]
}
```

As the loop runs, the variable `i` will take on the values 0, 1, 2, etc., up to but not including `array.length`. Inside the loop body, we can refer to the current array element using `array[i]`.

In other words, the above loop will execute the code between the curly braces once for each element in the array, with `array[i]` set to the current element in each iteration.

## Example

```javascript
let array = [1, 2, 3, 4, 5];

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

This will print:

```javascript
1
2
3
4
5
```

## Challenge Time!

Write a function called `sumArray` that takes an array of numbers as an argument and returns the sum of all the numbers in the array.

Example:

If we call `sumArray([1, 2, 3])`, the function should return `6`, because `1 + 2 + 3 = 6`.

Iterating over arrays - For

Example

Challenge Time!