Hidden Property Settings

Usually, an object's property is just a value. But actually, every property has " hidden " flags that dictate its behavior.

Three Main Flags:

1. writable: If true, the property can be changed.
2. enumerable: If true, the property shows up in loops (like for..in).
3. configurable: If true, the property can be deleted and its flags can be modified.

let user = { name: "John" };

Object.defineProperty(user, "name", {
  writable: false // Now the name cannot be changed!
});