Decorators in Python are powerful tools for modifying functions, methods, or class definitions, allowing developers to dynamically attach additional responsibilities without altering the original code structure. They serve as an alternative to subclassing for extending functionality and are useful for tasks like caching and access checking in web frameworks. Python uses the '@' symbol to apply decorators, which can be stacked to add multiple layers of functionality. Decorators maintain code that is more DRY (Don't Repeat Yourself) and encapsulated, making it reusable and easier to manage. Common decorators such as `@property`, `@staticmethod`, and `@classmethod` are integral to Python's built-in functions, while others like `contextlib.contextmanager` and `mock.patch` provide advanced capabilities for context management and testing. The article emphasizes the importance of practicing writing decorators to truly understand and utilize their potential, suggesting that hands-on coding is essential for mastering this concept.