SPF, which is an acronym for Sender Policy Framework, is an e-mail safety system, which is employed to confirm if an e-mail message was sent by an official server. Using SPF protection for a given domain will prevent the counterfeiting of emails made with the domain. In layman's terms: enabling this feature for a domain name creates a particular record in the Domain Name System (DNS) which contains the IP addresses of the servers that are allowed to send emails from mailboxes using the domain. As soon as this record propagates worldwide, it exists on all of the DNS servers that direct the Internet traffic. Whenever some e-mail message is sent, the first DNS server it uses checks whether it comes from an authorized server. If it does, it is forwarded to the destination address, yet if it doesn't come from a server indexed in the SPF record for the domain, it's discarded. In this way nobody will mask an email address and make it look as if you're distributing spam. This approach is also referred to as email spoofing.