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JavaScript JavaScript Loops, Arrays and Objects Tracking Multiple Items with Arrays Two-Dimensional Arrays

Posted by Jaymond Lockley
Jaymond Lockley
3,553 Points

What does [i] stand for?

Im not sure what it means .

Justyna Szofinska
Justyna Szofinska
6,178 Points
Justyna Szofinska
Justyna Szofinska
6,178 Points

This square bracket represent an array - multiple variable. When you create a loop with "i" variable you can put every number of the loop into "i". For example: 

function createListItem(arr){
let items=''; 
for (let i=0; i<arr.length; i++) {
 items += arr[i];
}
....

arr[i] means that during the loop we create arr[0],arr[1],arr[2] and so on until the loop will end.

1 Answer

Daniel Riches
Daniel Riches
19,847 Points
Daniel Riches
Daniel Riches
19,847 Points

I believe i stands for iteration. But within the bracket it corresponds to the array's index. So you're relating the loop iteration with the array index. For instance when i = 2, then the array index is also 2, i.e. array[2]