DKIM, which is an abbreviation for DomainKeys Identified Mail, is an email authentication system, which obstructs email addresses from being forged and email content from being tampered with. This is achieved by adding an e-signature to every message sent from an address under a specific domain. The signature is created on the basis of a private cryptographic key that is available on the outgoing SMTP server and it can be verified by using a public key, which is available in the global Domain Name System. Thus, any email with altered content or a forged sender can be recognized by mail service providers. This approach will boost your online safety dramatically and you’ll be sure that any message sent from a business collaborator, a banking institution, etc., is legitimate. When you send out messages, the receiver will also know for sure that you are indeed the one who has sent them. Any email that turns out to be fraudulent may either be flagged as such or may never reach the recipient’s mailbox, depending on how the given provider has chosen to treat such email messages.