Next to being converted to HTML and being published on the web, the most common mode of circulating a PDF is by email. Like other documents created in various programs such as Word or Excel, PDF files can be sent as an attachment either through your webmail or through Adobe Reader
All webmail servers such as Outlook, Yahoo!, and Gmail can attach PDFs to emails. In general, most webmail client functionality is similar. Thus, attaching a PDF follows the same basic method. In Adobe Reader, if you are connected to an email server, you can email the PDF you are viewing directly from the application.