DKIM, which is an abbreviation for DomainKeys Identified Mail, is an email validation system, which prevents email headers from being spoofed and email content from being manipulated. This is achieved by attaching an electronic signature to every message sent from an email address under a given domain name. The signature is created based on a private cryptographic key that’s available on the SMTP server and it can be validated by using a public key, which is available in the global DNS database. Thus, any email message with changed content or a spoofed sender can be identified by mail service providers. This approach will heighten your online safety immensely and you will be sure that any email message sent from a business ally, a bank, and so on, is a legitimate one. When you send messages, the receiver will also be sure that you are indeed the one who has sent them. Any email message that appears 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 handle such messages.