SPF, which is short for Sender Policy Framework, is an e-mail safety system, which is used to verify if an email message was sent by a certified server. Employing SPF protection for a given domain will stop the forging of emails created with the domain. In layman's terms: enabling this function for a domain name creates a specific record in the Domain Name System (DNS) which contains the IP of the servers which are permitted to send emails from mailboxes using the domain. Once this record propagates worldwide, it exists on all DNS servers that direct the Internet traffic. Any time an e-mail message is sent, the first DNS server it goes through checks if it comes from an accredited server. In the event it does, it is forwarded to the destination address, but if it doesn't come from a server indexed in the SPF record for the particular domain, it is discarded. In this way nobody will mask an email address and make it look as if you are distributing spam messages. This approach is also referred to as email spoofing.