What are some common design patterns found in JavaScript?

There are several common design patterns in JavaScript.

1. Factory Pattern: Creating objects through a factory method separates the object instantiation process from its usage, improving code maintainability and scalability.
2. Singleton Pattern ensures that a class has only one instance and provides a global access point to it.
3. Observer Pattern: Defines a one-to-many dependency relationship where multiple objects are notified and automatically updated when the state of one object changes.
4. The Publish/Subscribe Pattern is similar to the Observer Pattern, but it allows for decoupling between publishers and subscribers. Instead of publishers directly notifying subscribers, messages are passed through an intermediary component.
5. The Strategy Pattern defines a series of algorithms, encapsulates each algorithm into a class, and makes them interchangeable.
6. Adapter Pattern: It allows classes with incompatible interfaces to work together by converting the interface of one class into another interface that the client desires.
7. Decorator Pattern: dynamically adding additional responsibilities to an object without changing its original class.
8. Chain of Responsibility Pattern: Decouples the sender and receiver of a request, where each receiver contains a reference to the next receiver, forming a chain of responsibility.