freezingObjects.js

const array = [1, 2, 3];

array = [4, 5, 6]; // yes, it works! We can not mutate data but ...
array[0] = 4; // hmmm, now we have an alternative way to mutate data.

console.log(array); // returns [4, 2, 3]

Object.freeze(array); // The array cannot be modified.
array[0] = 1; // fails