DKIM, which is an acronym for DomainKeys Identified Mail, is a validation system, which stops email headers from being forged and email content from being tampered with. This is achieved by adding an e-signature to every email sent from an email address under a particular domain. The signature is issued based on a private encryption key that is available on the SMTP server and it can be verified by using a public key, which is available in the global DNS database. In this way, any email message with modified content or a forged sender can be recognized by mail service providers. This method will strengthen your web safety greatly and you’ll know for sure that any e-mail sent from a business partner, a bank, etc., is legitimate. When you send out emails, the receiver will also know for sure that you are indeed the one who has sent them. Any email message that turns out to be forged may either be marked as such or may never be delivered to the receiver’s mailbox, based on how the given provider has chosen to deal with such messages.