1- <ng-template> is a template element that Angular uses with structural directives like *ngIf, *ngFor, [ngSwitch] and custom directives
Note: the ng-template directive represents an Angular template
2- <ng-container> We can avoid having to create that extra div, we can instead use ng-container directive
<ng-container *ngFor="let item of items">
<p *ngIf="item.id">{{item.name}}</p>
</ng-container>3- *ngTemplateOutlet
We can used as a container to templates that can be reused at multiple places.