Adobe Acrobat 7 Professional - Manual (Page 497)

About file attachments
Acrobat lets you attach PDF and other files to an Adobe PDF document so that the reader
can open them for viewing. If you move the PDF document to a new location, the
attachments automatically go with it. You can add two types of file attachments to PDF
documents from the File toolbar: document-level attachments and page-level attachments.
Document-level attachments are added by using the Attach A File tool and may
include links to or from the parent document or to other file attachments. (See Linking
between files .) Page-level attachments are added as comments by using various tools to
add sound files and documents. (See Adding attachments as comments .) Comment, or
page-level, attachments display the File Attachment icon or the Speaker icon on
the page where they're located.
If a PDF document contains an attachment, the File Attachment icon appears in the
status bar. You can view a tool tip with the total number of attachments by placing the
pointer over the icon. The Attachments tab lists all the attachments in the PDF document,
including the name, a description, the modification date, and the file size. Page-level
attachments also include the page number of their location.
Use the Attachments tab to add, delete, or view attachments.