Are imported items saved locally in file or referenced?

If I have a component that has some inported components are those inserted components saved locally to the file, or are they just referenced to their own file.

In other words. If I a component (file) and I send only that file to someone. When they open it will the imported objects still be there?

Thanks,
Joe

Yes, they are embedded in the file (with info about where they came from so that they can be refreshed later).