new

When we do:

function Person(username) {
    this.name = username
}

const userOne = new Person("Chandan")

JavaScript does four things automatically behind the scenes.

1. Creates a New Object

const obj = {}

2. Links It to the Prototype

The new object gets connected to Person.prototype so it can inherit methods from it.

obj.__proto__ = Person.prototype

3. Calls the Function with this

The constructor function runs with this pointing to the newly created object.

Person.call(obj, "Chandan")

4. Returns the Object Automatically

return obj;