Dependency Injection
Dependency Injection is a software design pattern and technique in which an object receives its dependencies from an external source rather than creating them internally. It promotes loose coupling between components by separating the creation of dependencies from their usage, making code more modular, testable, and maintainable. This is commonly implemented through constructors, setters, or interfaces to inject dependencies.
Developers should learn Dependency Injection to build scalable and testable applications, especially in complex systems like enterprise software or microservices architectures. It is crucial when using frameworks like Spring (Java) or Angular (TypeScript) to manage object lifecycles and reduce boilerplate code. By decoupling components, it simplifies unit testing through mock dependencies and enhances code reusability.