Final answer:
A decorator is a design pattern used in object-oriented programming to add new functionality to an existing object without modifying its structure. They provide a flexible way to modify the behavior of individual objects without affecting the entire class hierarchy.
Step-by-step explanation:
The purpose of a decorator in programming is to modify or enhance the behavior of functions or classes without permanently modifying their structure. Decorators wrap a function or class to provide additional functionality, acting in many ways as a wrapper. Despite the initial confusion, decorators are not used to achieve encapsulation as suggested by the question, which is more specifically a technique in object-oriented programming for restricting access to certain components of an object.
A decorator is a design pattern used in object-oriented programming to add new functionality to an existing object without modifying its structure. It is similar to a class and is used to achieve encapsulation. The purpose of a decorator is to extend the behavior of an object dynamically at runtime.
Decorators can be used to add new features or modify the behavior of an object, such as adding additional methods or attributes, enhancing existing methods, or wrapping the object with additional functionality. They provide a flexible way to modify the behavior of individual objects without affecting the entire class hierarchy.
For example, let's say we have a class called 'Car' which has basic functionalities like start, stop, and accelerate. We can use a decorator to add new features to this class, such as a 'GPS' decorator to provide navigation functionality or an 'Airbag' decorator to add safety features. This allows us to add or remove these functionalities as needed, without having to modify the original class.