Check out example codes for "ngTemplate". It will help you in understanding the concepts better.

Code Example 1

<div *ngIf='name && lastName; then thereAreParams else thereArentAnyParams'>

</div>

<ng-template #thereAreParams>
  <h2>Name is : {{name}} </h2>
   <h2>Last name is : {{lastName}} </h2>
</ng-template>

<ng-template #thereArentAnyParams>
  <h2>There aren't any parameters</h2>
</ng-template>

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