Am I correct in thinking this?

JavaScript
1

Is it correct to think like this:

(n) means the number of elements
[n] means the index

I just get confused about when a number is actually a number/counting something normally as opposed to an index where we have to count from 0.

Many thanks.

2

It depends on the context. [n] is probably referring to an index, but it depends on where you’re seeing (n).