What is the difference between saved reports and scheduled reports?

Saved reports are stored in the system with the settings you used when you ran and saved them. You can run the saved reports when you want to see updated data, but you do not have to set the parameters every time.
Scheduled reports are saved reports that you have also setup to automatically run at the specified intervals. Scheduled reports are sent as PDF, Excel, or Data (.csv) e-mail attachments to the appropriate users via email.