| Abstract Factory | Creational | Provides an interface for creating families of related or dependent objects without specifying their concrete classes. |
| Builder | Creational | Separates the construction of a complex object from its representation, allowing the same construction process to create different representations. |
| Factory Method | Creational | Defines an interface for creating an object, but lets subclasses alter the type of objects that will be created. |
| Prototype | Creational | Specifies the kinds of objects to create using a prototypical instance, and creates new objects by copying this prototype. |
| Singleton | Creational | Ensures a class has only one instance and provides a global point of access to it. |
| Adapter | Structural | Converts the interface of a class into another interface clients expect, allowing classes to work together that couldn’t otherwise because of incompatible interfaces. |
| Bridge | Structural | Decouples an abstraction from its implementation so that the two can vary independently. |
| Composite | Structural | Composes objects into tree structures to represent part-whole hierarchies, allowing clients to treat individual objects and compositions of objects uniformly. |
| Decorator | Structural | Attaches additional responsibilities to an object dynamically, providing a flexible alternative to subclassing for extending functionality. |
| Facade | Structural | Provides a unified interface to a set of interfaces in a subsystem, making the subsystem easier to use. |
| Flyweight | Structural | Uses sharing to support large numbers of fine-grained objects efficiently. |
| Proxy | Structural | Provides a surrogate or placeholder for another object to control access to it. |
| Chain of Responsibility | Behavioral | Avoids coupling the sender of a request to its receiver by giving more than one object a chance to handle the request. |
| Command | Behavioral | Encapsulates a request as an object, thereby allowing for parameterization of clients with queues, requests, and operations. |
| Interpreter | Behavioral | Given a language, defines a representation for its grammar along with an interpreter that uses the representation to interpret sentences in the language. |
| Iterator | Behavioral | Provides a way to access the elements of an aggregate object sequentially without exposing its underlying representation. |
| Mediator | Behavioral | Defines an object that encapsulates how a set of objects interact, promoting loose coupling by keeping objects from referring to each other explicitly. |
| Memento | Behavioral | Without violating encapsulation, captures and externalizes an object’s internal state so that the object can be restored to this state later. |
| Observer | Behavioral | Defines a one-to-many dependency between objects so that when one object changes state, all its dependents are notified and updated automatically. |
| State | Behavioral | Allows an object to alter its behavior when its internal state changes, making the object appear to change its class. |
| Strategy | Behavioral | Defines a family of algorithms, encapsulates each one, and makes them interchangeable, allowing the algorithm to vary independently from clients that use it. |
| Template Method | Behavioral | Defines the skeleton of an algorithm in an operation, deferring some steps to subclasses, allowing them to redefine certain steps without changing the algorithm’s structure. |
| Visitor | Behavioral | Represents an operation to be performed on the elements of an object structure, allowing new operations to be defined without changing the classes of the elements on which it operates. |