Dependency Injection or DI, in Angular, is a term that represents a design pattern in which class requests dependencies, from external sources. These design patterns don’t allow the classes to create these dependencies themselves. In short, these DIs enable the ability to add functionality to the components at the runtime environment.
Wish to learn Angular and master it? Check out the Angular JS course from Intellipaat, which offers you the instructor-led training course and guided projects to help you get started. Also, watch the below video on Angular JSTutorial for Beginners, if you are just starting out.