Pass by value

Copy is made in memory.

New memory allocation is done.

• all the changes are made to the new value/memory location.

let num1 = 70;
let num2 = num1;

console.log(num1) // 70
console.log(num2) // 70

num1 = 40

console.log(num1) // 40
console.log(num2) // 70

Pass by reference

Does NOT create a new space in memory.

• passes the reference/address pointer of the original memory.

const obj1 = {website: "Scaler Academy"}
const obj2 = obj1;

console.log(obj1); // {website: "Scaler Academy"}
console.log(obj2); // {website: "Scaler Academy"}

obj1.website = "Scaler Topics"

console.log(obj1); // {website: "Scaler Topics"}
console.log(obj2); // {website: "Scaler Topics"}