Services allow greater separation of concerns in Angular applications. They also provide modularity by allowing developers to extract common functionalities out of components. Adding Services to Angular applications makes components free from data access code.

 

Service has the following features:

  • Singleton, i.e. only one instance of service will exist throughout the application.
  • Capable of returning data in the form of Observables and promises.
  • Decorated with @Injectable() decorator
BY Best Interview Question ON 13 Jan 2019