DKIM, which is short for DomainKeys Identified Mail, is an authentication system, which stops email addresses from being spoofed and email content from being tampered with. This is achieved by attaching a digital signature to each email message sent from an address under a given domain name. The signature is created on the basis of a private cryptographic key that’s available on the sending server and it can be validated with a public key, which is available in the global Domain Name System. In this way, any email message with changed content or a spoofed sender can be spotted by mail service providers. This approach will increase your worldwide web security dramatically and you’ll know for sure that any email message sent from a business associate, a banking institution, etc., is a genuine one. When you send email messages, the receiver will also be sure that you are indeed the one who has sent them. Any mail that turns out to be bogus may either be flagged as such or may never show up in the receiver’s mailbox, depending on how the particular provider has chosen to cope with such emails.