What are design patterns? Explain some of them and their use cases.

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Accepted Answer

Design patterns are reusable solutions to common software design problems, enhancing code maintainability and scalability.

Singleton Pattern: Ensures a class has only one instance, e.g., a configuration manager in an application.
Observer Pattern: Allows objects to subscribe and react to events, e.g., a stock price alert system.
Factory Pattern: Creates objects without specifying the exact class, e.g., a vehicle factory producing different types of vehicles.
Decorator Pattern: Adds new functionality to existing objects, e.g., adding extra features to a coffee order in a café.

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