Explain the concept of dependency injection in Kotlin and its role in building scalable applications.

Dependency injection (DI) is a design pattern and a concept widely used in software development, including Kotlin, to achieve loose coupling between components and improve the modularity and testability of an application. It involves externalizing the dependencies required by a class and providing them from external sources rather than the class itself creating or managing them. In Kotlin, dependency injection is commonly implemented using frameworks such as Dagger, Koin, or manual DI techniques. Here's an in-depth explanation of the concept and its benefits: 1. Dependency Injection Principles: Dependency injection follows several key principles: * Inversion of Control (IoC): The control over creating and managing dependencies is shifted from the class itself to an external entity, typically a DI container or framework. * Single Responsibility Principle (SRP): Classes should have a single responsibility, and the responsibility of creating and managing dependencies is delegated to another component. * Dependency Inversion ....