Hi,
Digital signature is a technique used for secure transfer of information over the internet. The technology works something like this:
Your message is encoded with some secret key to produce message digest (signed message).. The reciever has to decode the original message with another key (pre-provided by the sender).. If the decryption goes on fine, then u can be sure that it was signed by that particular person.
Visit
www.verisign.com for further details
Madhesh