Inheritance and composition

1. Inheritance allows subclasses to have various properties and methods of the parent class without having to write the same code again. While the subclass inherits the parent class, you can re-

Define some properties and override some methods, overriding the original properties and methods of the parent class so that they have different functionality than the parent class. Also known as "white box-type complex

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2, combination, refers to the existing objects by combining rest their lives new more complex functions, because between the objects, the internal details are not visible, the

We also say that code reuse in this way is "black-box code reuse."

Inheritance and composition