DKIM, which is short for DomainKeys Identified Mail, is a validation system, which impedes email addresses from being spoofed and email content from being meddled with. This is done by adding an electronic signature to each email sent from an address under a given domain name. The signature is created based on a private cryptographic 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 Domain Name System. In this way, any email message with modified content or a spoofed sender can be identified by email providers. This technology will increase your online security substantially and you’ll know for sure that any e-mail sent from a business associate, a bank, and so on, is legitimate. When you send out emails, the recipient will also be sure that you are indeed the one who has sent them. Any email message that turns out to be forged may either be labeled as such or may never appear in the recipient’s mailbox, depending on how the given provider has decided to cope with such emails.