NaN - not a number. This means that you are not trying to add numbers, but strings. If you add 1 + 1, it will be 2, and if “1” + 1 or " 1 " + “1”, it will be NaN. How do I add “1” + “1”? To do this, you need to convert a number in string form to a number, for example, using the addition block with 0.
