DKIM, which is short for DomainKeys Identified Mail, is an authentication system, which impedes email headers from being forged and email content from being modified. This is done by attaching a digital signature to each and every email sent from an address under a specific domain name. The signature is published on the basis of a private key that is available on the outgoing SMTP server and it can be validated using a public key, which is available in the global DNS database. Thus, any email with modified content or a forged sender can be recognized by email providers. This technology will increase your online security significantly and you’ll know for sure that any e-mail message sent from a business associate, a banking institution, and so on, is genuine. When you send messages, the receiver will also be sure that you are indeed the one who has sent them. Any email that appears to be counterfeit may either be marked as such or may never be delivered to the receiver’s inbox, based on how the given provider has decided to deal with such messages.