DKIM, which is short for DomainKeys Identified Mail, is an authentication system, which impedes email headers from being spoofed and email content from being manipulated. This is achieved by attaching an e-signature to every email sent from an email address under a certain domain. The signature is issued based on a private cryptographic key that is available on the SMTP mail server and it can be verified with a public key, which is available in the global DNS database. In this way, any message with modified content or a spoofed sender can be identified by email service providers. This technology will increase your web safety significantly and you’ll be sure that any email sent from a business partner, a bank, etc., is legitimate. When you send out messages, the recipient will also know for sure that you are indeed the one who has sent them. Any email message that turns out to be phony may either be flagged as such or may never show up in the recipient’s mailbox, depending on how the particular provider has decided to deal with such emails.