SPF, which means Sender Policy Framework, is an email protection system, which is employed to confirm whether an email message was sent by an official server. Employing SPF protection for a domain name will stop the counterfeiting of emails made with the domain. In layman's terms: enabling this attribute for a domain name makes a particular record in the Domain Name System (DNS) which contains the IP of the servers which are permitted to send e-mail messages from mail boxes using the domain. When this record propagates worldwide, it will exist on all of the DNS servers that direct the Internet traffic. When a new e-mail message is sent, the initial DNS server it uses verifies if it comes from an accredited server. When it does, it's sent to the destination address, however if it does not originate from a server listed in the SPF record for the domain, it's discarded. In this way nobody will mask an e-mail address and make it look as if you are distributing spam. This approach is also called email spoofing.