You should learn design patterns because they give you proven, reusable solutions to common software design problems. Instead of reinventing the wheel every time, patterns help you write code that is clean, scalable, flexible, and easy to maintain. They teach you how to think in structures, not just syntax — making it easier to communicate with other developers, architect complex systems, and avoid spaghetti code. Whether you're working on a small app or a big enterprise system, design patterns help you build software that lasts.

And here are top 10 of them you should start learning now.

1. Factory Pattern

Creates objects without exposing the instantiation logic to the client.
Used when you want to delegate the creation of objects to a single point — instead of scattering new Class() everywhere.

2. Strategy Pattern

Enables selecting an algorithm at runtime by encapsulating each behavior in a separate class. Avoids if-else/switch by letting you swap logic like payment methods or sorting strategies dynamically.

3. Singleton Pattern

Ensures a class has only one instance and provides global access to it. Perfect when one shared thing (like a database connection or logger) needs to be accessed everywhere.

4. Observer Pattern

Defines a one-to-many dependency so that when one object changes state, all its dependents are notified. Aka event listeners — used in UI, notifications, activity logs.

5. Decorator Pattern

Adds new behaviors to objects dynamically without changing their structure. Wrap an object to extend its functionality (great alternative to subclassing).

6. Adapter Pattern

Converts the interface of a class into another interface that a client expects. Useful for integrating incompatible systems or third-party APIs.

7. Builder Pattern

Constructs complex objects step-by-step, allowing different representations using the same construction process. Best for creating objects with many optional parameters.

8. Facade Pattern

Provides a simplified, unified interface to a complex subsystem. Hides all the complexity behind one simple class/interface.

9. Command Pattern

Encapsulates a request as an object, allowing it to be queued, logged, or undone. Perfect for systems where actions can be delayed, repeated, or undone.

10. Chain of Responsibility Pattern

Passes a request along a chain of handlers until one handles it. Each handler decides whether to handle the request or pass it along.