OOP principles support

The second requirement that allows us to consider JavaScript as an Object-Oriented language involves the support of at least three principles—encapsulation, inheritance, and polymorphism. Let analyze how JavaScript supports each of these principles.

Encapsulation

Objects are central to the Object-Oriented Programming model, and they represent the typical expression of encapsulation, that is, the ability to concentrate in one entity both data (properties) and functions (methods), hiding the internal details.

In other words, the encapsulation principle allows an object to expose just what is needed to use it, hiding the complexity of its implementation. This is a very powerful principle, often found in the real world that allows us to use an object without knowing how it internally works. Consider for instance how we drive cars. We need just to know how to speed up, brake, and change direction. We do not need to know how the car works in detail, how its motor burns...