Class

In this chapter, you will the learn the basics of a class and how to define them in a program. We will look at the concept of car and how to represent a car in a program.

Concept of Car

A car has attributes such as color, price, model and so on. You can exercise certain behavior such as drive, stop, turn, etc on a car.

Representing a Car

We can represent the concept of a car using a class.

A class has a class name. In this example, the class name is Car.

Defining a Class

Let's define a Car class.

class Car
end

We use the class keyword followed by the class name to define a class. In this case, Car is the class name.

Representing the Behavior

We can represent the drive behavior of a car by defining a drive() method for the Car class.

class Car
  def drive()
    return 'driving'
  end
end

The methods provide the behavior for the objects. We use the def keyword followed by the method name to define a method. The body of the method becomes the implementation.

Car Class Analogy

A Car class is like a car blueprint.

A car blueprint is used to manufacture many cars.

• A car class acts as a template used to create cars.
• A car class describes the behavior and attributes of a car.

Define a method in the Car class to stop a car.

Summary

In this chapter, you learned the concept of class. A class describes the behavior and attributes of a certain concept.