A memorandum of beginners.
I was a little confused about the relationship between the parent class and the child class, and the relationship between the class and the instance.
All four are objects, and objects are concepts that include classes.
○ Relationship between class and instance -Based on the class, an "object" called an instance is created. -Methods defined in the class can be called like "instance.method". -Instance variables defined in a class, such as @ 〇〇〇, can also be called in an instance.
○ Relationship between parent class and child class -A new "class" called a child class is created based on the parent class. -In the child class, the method defined in the parent class can be changed by defining the method with the same name (override).