How does Calendar handle file attachments?
Through Calendar, you can add attachments to groups so that users can view the files associated with the group, such as a contact list. You can also add attachments to events so you can send files associated with the event to the invitees, such as a meeting agenda.
When you add an attachment to an event, the file is sent with the invitation as an attachment in the email message.
You can add files as attachments from your Online Storage, if you have one, or from your computer.