What is the role of inheritance in object-oriented programming?

Inheritance in object-oriented programming allows classes to derive properties and methods from other classes.

Inheritance is a fundamental concept in object-oriented programming (OOP) that facilitates code reusability and modularity. It is a mechanism where a new class, known as a subclass or derived class, is created from an existing class, known as a superclass or base class. The derived class inherits all the features of the base class and can also add new features or override the inherited ones.

The primary advantage of inheritance is that it promotes code reusability. Instead of writing the same code again and again, a subclass can simply inherit the properties and methods of a superclass. This not only saves time and effort but also makes the code more readable and maintainable.

Inheritance also supports the representation of real-world relationships in programming. In the real world, we often deal with categories and subcategories. For instance, a 'Car' is a type of 'Vehicle', and a 'Sports Car' is a type of 'Car'. These relationships can be easily modelled in OOP using inheritance, where 'Vehicle' would be a base class, 'Car' would be a subclass of 'Vehicle', and 'Sports Car' would be a subclass of 'Car'.

Moreover, inheritance provides a framework for polymorphism, another key concept in OOP. Polymorphism allows objects of different classes to be treated as objects of a common superclass. This can greatly simplify code and make it more flexible.

However, it's important to use inheritance judiciously. Overuse of inheritance can lead to a complex class hierarchy that is hard to understand and maintain. Also, since a subclass inherits all properties and methods of a superclass, it can lead to unwanted side effects if the superclass changes. Therefore, it's often recommended to favour composition (combining simple objects to create more complex ones) over inheritance where possible.

In conclusion, inheritance is a powerful tool in object-oriented programming that, when used correctly, can greatly enhance code reusability, modularity, and readability.