ITP2 - OOP Tutorials - Classes and Objects

The initialize method gets called every time you create a new object.
That's odd, don't we call the new method when we create an object? Yes,
calling the new class method eventually leads us to the initialize
instance method. We'll talk about the difference between class methods
and instance methods later. In the above example, instantiating a new
GoodDog object triggered the initialize method and resulted in the
string being outputted. We refer to the initialize method as a
constructor, because it gets triggered whenever we create a new object.