At the moment you're assigning the just code structure of the function
When you do this you're not executing the function in any way. That's why when you
console.log(newNumber) it shows the string representation of the function. If you were to instead do
console.log(newNumber(8)) then you would be calling the function. Big difference whether you include the parentheses or not.
However with that being said I think you're meant to do:
var newNumber = timesTwo(8);
Doing it this way will avoid the unnecessary transferal of code sructure from one variable to another and instead just call the
timesTwo function straight away and assign the return value to
Hope that makes sense.