java print out

Question

hey guys, I was just paying with some codes and I realized if I don't use the "+" sign after I in princesses in the "document.write" it will show me an error!!
what is the purpose of that plus sign?
the code is:
var i = 0;
for (; i <= 10; ) {
document.write(i+ "<br />");
i++;
}

Answer 1

As i is a number and <br /> is a html tag, + sign is needed to *join* them together.
Even if the former would be a string, then also we had used + as both are two unique elements!

Answer 2

thank you blue for your awesome explanation 😊