product-list.component.ts

import { Component } from '@angular/core';

@Component({
   selector: 'pm-products',
   templateUrl: './product-list.component.html'
})

export class ProductListComponent {
   pageTitle: string = 'Product List';
}

app.component.ts

import { Component } from '@angular/core';

@Component({
   selector: 'pm-root',
   template: `
   <div><h1>{{pageTitle}}</h1>
      <pm-products></pm-products>
   </div>
   `
})

export class AppComponent {
   pageTitle: string  = 'Product Management';
}