_Different ways to structure classes in TypeScript, when to use each pattern, and common design patterns._

| File | Topic | One-line |

| ---------------------------------------------- | ----------------- | -------------------------------------------------------------- |

| [abstract-classes.md](./abstract-classes.md) | Abstract Classes | Base classes that cannot be instantiated directly |

| [decorator-pattern.md](./decorator-pattern.md) | Decorator Pattern | Attach new behaviors to objects via wrapper objects |

| [factory-pattern.md](./factory-pattern.md) | Factory Pattern | Interface for creating objects in a superclass |

| [observer-pattern.md](./observer-pattern.md) | Observer Pattern | Subscription mechanism to notify multiple objects about events |

| [regular-classes.md](./regular-classes.md) | Regular Classes | Multiple instances with independent state and behavior |

| [singleton-pattern.md](./singleton-pattern.md) | Singleton Pattern | Exactly one instance with global access point |

| [static-classes.md](./static-classes.md) | Static Classes | Utility classes with only static members, no instances needed |

_This series covers TypeScript class structures from basic instances to advanced design patterns, helping you choose the right approach for every coding scenario._