function changeValue() { // Call by Value
	let dream = 10;
	console.log(dream);
}

function changeName(obj) { // Call by Reference
  obj.name = 'coder';
	console.log(obj);
}

let dream = 4;
const ellie = {name: 'ellie'};

changeValue();      // 10
console.log(dream); // 4

changeName(ellie);  // { name: "coder" } (name: 'ellie' -> name: 'coder')
console.log(ellie); // { name: "coder" }