Pdf allows you to view Adobe Acrobat or Portable Document Format (PDF) files on your EPOC PDA. Pdf is available in two flavors, 'plain' Pdf and Pdf+. 'Plain' Pdf is free, but Pdf+ can do a lot more.
Pdf will display the text, the line drawings and the pictures inside the file on the screen or (Pdf+ only) on a printer. You can also go to a certain page, search for words in the text of a document, and (Pdf+ only) copy a piece of text to another program.
With Pdf+ you can also view encrypted files, protected by a user password, for extra security. If the file contains links to other pages, you can follow a link to it's destination by tapping on it. Pdf+ even starts a web browser if the link is a web address. If the file contains bookmarks, Pdf+ shows them in a separate view. You can jump to a bookmark too, just by tapping on it.
Pdf+ also has special modes for the Psion Revo and Revo Plus, and Series 7/netBook, to optimise screen usage on those machines.
OK, so you want to stamp your document. Maybe you need to give reviewers some advice about the document's status or sensitivity. This tip from author Ted Padova demonstrates how to add stamps with the Stamp Tool along with related comments.