Why is [1,2] + [3,4] = “1,23,4” in JavaScript?

Question

I wanted to add the elements of an array into another, so I tried this:

[1,2] + [3,4]

It responded with:

\"1,23,4\"
         


        

Answer 1

It adds the two arrays as if they were strings.

The string representation for the first array would be "1,2" and the second would be "3,4". So when the + sign is found, it cannot sum arrays and then concatenate them as being strings.