component.ts

// New instance of the service with new instance of the component
@Component({
  selector:    'app-component',
  templateUrl: './app-component.component.html',
  providers:  [ MyService ]
})
export class Component {
  constructor(private serive: MyService) {}
}

// Same intance of the service available to all components
@NgModule({
  imports:      [ Component ],
  declarations: [ AppComponent, Component ],
  bootstrap:    [ AppComponent ],
  providers: [ MyService ]
})
export class AppModule { }