OK, after a bit more reading I now understand the difference, thank you for your patience. But it remains true that in Javascript you can not pass an object by

OK, after a bit more reading I now understand the difference, thank you for your patience. But it remains true that in Javascript you can not pass an object by value, because the language does not permit creating copies of objects. You can only ever pass a reference to an object (which is indeed only ever done by value) so the usefulness of arguing about the distinction is questionable at best.