40input and 40output in angular

1Input is used to receive data in whereas Output is used to send data out.	
2Output sends data out by exposing event producers, usually EventEmitter objects.	
3@Component({
4  selector: 'todo-item',
5  ...
6})
7export class TodoItemComponent {
8  @Input()  item
9  @Output() onChange = new EventEmitter()
10}