What Is Router imports?
It is an optional service that presents a special component view for a given URL. It has own library package- @angular/router and It is not a part of an Angular core.
The Angular package looks like this.
import {Routes, RouterModule,} from '@angular/router';
And
//Composability and Grouping
//imports used for composing modules together.
imports: [
BrowserModule,
//enableTracing enables debugging purposes only
//useHash enables the location strategy that uses the URL fragment instead of the history API.
RouterModule.forRoot(appRoots, { enableTracing: true, useHash:true })
],
For
more detail kindly refer the link - https://www.code-sample.com/2018/05/angular-5-6-7-routing-and-navigation.html