DKIM, which is short for DomainKeys Identified Mail, is an email authentication system, which obstructs email headers from being forged and email content from being meddled with. This is done by attaching an e-signature to each and every email sent from an address under a particular domain name. The signature is issued on the basis of a private key that is available on the outgoing SMTP server and it can be validated by using a public key, which is available in the global DNS database. In this way, any message with changed content or a spoofed sender can be identified by email service providers. This approach will enhance your online safety tremendously and you will know for sure that any message sent from a business associate, a bank, and so on, is genuine. When you send email messages, 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 counterfeit may either be marked as such or may never appear in the receiver’s mailbox, based on how the given provider has chosen to deal with such email messages.