Abstraction

Definition#

Abstraction is a technique used in object-oriented programming that simplifies the program's structure. It focuses only on revealing the necessary details of a system and hiding irrelevant information to minimize its complexity. In simpler words, we can say that it means to show what an object does and hides how it does it.

Example#

There are countless real-life examples that follow the rules of abstraction. Take the "volume" button on a television remote. With one click, we can increase the TV’s volume. Let’s say the button calls the volumeUp() function. The TV responds with a sound louder than before. We are oblivious to the fact that the inner circuitry of the TV implements this, but we know how the exposed function interacts with the TV's volume.

Another instance of abstraction is our daily use of vehicles. To our general knowledge, the race peddle tells the car to consume fuel and increase its speed. We do not need to understand the mechanical process.

Implementation of abstraction in programming languages#

So, let’s put all this theory into practice. In the code below, we have a basic class of a circle:

It has two variables, radius and pi. Now let’s add the constructor and functions to calculate the area and perimeter:

As you can see, we only need to define the radius of the circle in the constructor. After that, the area() and perimeter() functions are available to us. This interface is part of encapsulation.

We use the functions to calculate the area and perimeter. Users do not need to know the implementation details of the functions. Even pi is hidden since it’s a constant. This is how we can achieve abstraction using classes.

Advantages of abstraction#

The following are some advantages of abstraction:

• It reduces the complexity of the system from a user's perspective.

• It makes the code extendable and reusable.

• It refines the modularity of the application or the system.

• It makes the code more maintainable.

Abstraction vs. encapsulation#

Since abstraction and encapsulation are data hiding techniques of OOP, they are often confused with being the same. Let's look at some of the differences in the following table:

Next, let's look at another important principle of object-oriented programming—inheritance.