Why am I getting NaN?

var message="in global";
console.log("global: message = " + message);

var a = function() {
    var message= "inside a";
    console.log("a: message = " + message);
    b();
}

function b() {
    console.log("b: message = ", + message);
}

a();

Expected output:
global: message = in global
a: message = inside a
b: message = inside global
Actual output:
global: message = in global
a: message = inside a
b: message = NaN

Can anyone please explain why the expected and actual output is differing?

idk JAVA (ig this is JAVA) but why don’t you write this –

like this —

or something since it’s working for a: message ?

Thanks!!

function b() {
    console.log("b: message = ", + message);
}

Why , before + ?

incorrect:
function b() {
console.log("b: message = ", + message);
}

Correct:
function b() {
console.log("b: message = " + message);
}

Remove , Before +