What is data-bound properties?

When you have a component

@Component({
  selector: 'my-component'
})
class MyComponent {
  @Input() name:string;

  ngOnChanges(changes) {
  }

  ngOnInit() {
  }
}

you can use it like

<my-component [name]="somePropInParent"></my-component>

This make name a data-bound property.

When the value of somePropInParent was changed, Angulars change detection updates name and calls ngOnChanges()

After ngOnChanges() was called the first time, ngOnInit() is called once, to indicate that initial bindings ([name]="somePropInParent") were resolved and applied.

For more details see https://angular.io/docs/ts/latest/cookbook/component-communication.html