Prototypal Inheritence

In programming,sometimes we want to extend something.
For instance:
we have one object which is named as a someuser with some properties and methods and on the other hand we have anpther object with its own attributes and properties. we`d like to reuse what we have in someuser object not copy its methods. Prototypal inheritance is a language feature that helps in that.
In JavaScript, objects have a special hidden property [[Prototype]] (as named in the specification), that is either null or references another object. That object is called “a prototype”:

1let animal={
2    eats:true  
3}
4let fruit={
5    Apple:"i am Apple"
6}
7fruit.__proto__=animal
8console.log("Welcome !",fruit.eats);
9

If we look for a property in rabbit , and it’s missing, JavaScript automatically takes it from nimal .
For instance:

1
2  let nimal = {
3    eats: true,
4    walk() {
5    alert("Animal walk");
6    }
7    };
8    let rabbit = {
9    jumps: true,
10    __proto__: nimal
11    };
12  

The prototype chain can be longer:

Imagine, we got a stringified meetup object from the server. It looks like this:
And now we need to deserialize it, to turn back into JavaScript object. Let’s do it by calling JSON.parse Let’s pass to JSON.parse the reviving function as the second argument, that returns all values “as is”, but date will become a Date :

1
2  let nimal = {
3    eats: true,
4    walk() {
5    alert("Animal walk");
6    }
7    };
8    let rabbit = {
9    jumps: true,
10    __proto__: nimal
11    };
12    let dog = {
13        jumps: true,
14        __proto__: mammal
15        }; 
16console.log("animal is",dog.eats) // Animal walk
17  

1let memal1 = {
2    eats: true,
3    walk() {
4    alert("Animal walk");
5    }
6    };
7    let memal2 = {
8    jumps: true,
9    __proto__: memal1
10    };
11    let memal3 = {
12    earLength: 10,
13    __proto__:memal2
14    };
15    console.log("hi",memal3.eats)
16