ionic3, differences between NavController and Nav, from package 'ionic-angular'

in ionic doc link i have NavController:

https://ionicframework.com/docs/api/navigation/NavController/

import { Component, ViewChild } from '@angular/core';
import { NavController } from 'ionic-angular';

@Component({
   template: '<ion-nav #myNav [root]="rootPage"></ion-nav>'
})
export class MyApp {
   @ViewChild('myNav') nav: NavController

and in my ionic3 project installing with 'ionic start myionic3' with template 'super' the app.component.ts have:

...
import { Platform, Nav, Config } from 'ionic-angular';
...
export class MyApp {
  public rootPage: any = LoginPage;

  @ViewChild(Nav) nav: Nav;
...

why there are differents, ionic doc site is outdated ?