Roshan K.

Let's ask ourselves what a Service is ? Well under the hood, just a glorified module which exposes a few classes that you import in your component via the normal import - import { Http, Response, RequestOptions, Headers } from '@angular/http'; However this is more like injecting the service. What about registering it? So we start with a normal import into the module . But then you don't see an entry into the providers in the module. Reason being that the provider configuration for Http isn’t so straight forward, so the Angular team have given us a handy way to configure our NgModule with all the required providers for Http and that is adding to the imports section. Importing HttpModule into our NgModule configures our NgModules injector with all the providers needed to use Http in our app. So to summarize the first import is registering and the second is injecting.