Why angular model interfaces are exported?

In angular – the models (model interfaces) are declared like so:

export interface PersonInterface {
  id: number;
  name: string;
}

and then in some other component,service etc. your import this interface and use it like so:

...
import { PersonInterface } from './blabla';
...
export class SomeService {
  person: PersonInterface;
}

So my question is – what is the purpose of using export in the declaration of the interface?

interface PersonInterface {
  id: number;
  name: string;
}

If I don’t use export – I can still use it in the service and I even do not need to import it:

export class SomeService {
  person: PersonInterface;
}

Everything works fine, no errors and from the IDE I can go to the declaration if the interface (Ctrl+Click over the interface name). Am I missing something?

Cheers

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