Swift Inheritance Explained: Subclasses, Override, and the Final Keyword

Swift's inheritance feature allows a subclass to acquire all properties and methods of a parent class while adding its own unique behaviour. Using a colon followed by the parent class name, a subclass gains everything the superclass defines without duplicating code. When a subclass needs a different version of an inherited method, the override keyword must be used explicitly, preventing accidental silent replacements. Swift uses the actual runtime type of an object to determine which version of an overridden method to call. The final keyword can be applied to prevent a class or specific method from being subclassed or overridden further.