There is a very hard to understand concept which JavaScript has called Prototype. You've already seen a lot if you have an experience with JavaScript. Many books and articles describing prototype are out

You've probably seen the Object.create pattern was used to mimic Classical inheritance in JavaScript ES5 such as: function Animal() { } Animal.prototype.say = function() { console.log('Say!'); }; function

As you know, There was only var keyword for variable declaration before ES2015. but Modern JavaScript have introduced let and const keywords for it. So let's figure out the differences between var and