what is document open password?

Hi vikychopade,

Document password is used to limit people to view the contents inside the document.

Video's below will provide more information about document password and how to use.

http://tv.adobe.com/watch/acrobat-x-tips-tricks/how-do-i-password-protect-a-document/

http://tv.adobe.com/watch/acrobat-tips-and-tricks/protecting-your-pdf-using-a-password/