title: How to digitally sign a pdf using iText?
body: <p>How do i sign a pdf using iText ? I'am going through this <a href="http://itextpdf.sourceforge.net/howtosign.html" rel="nofollow">LINK</a>  but didn't understand about my_private_key.pfx. Do i really need a certificate for digital signature ? Please clarify me. Thanks in advance.</p>