SPF, which stands for Sender Policy Framework, is an email protection system, which is employed to verify whether an e-mail message is sent by an official server. Using SPF protection for a particular domain will prevent the faking of emails made with the domain. In layman's terms: activating this function for a domain name makes a particular record in the Domain Name System (DNS) which includes the IP addresses of the servers which are permitted to send email messages from mail boxes using the domain. Once this record propagates globally, it will exist on all DNS servers that direct the Internet traffic. Every time some e-mail message is sent, the first DNS server it uses verifies if it comes from an approved server. When it does, it's forwarded to the destination address, however if it doesn't originate from a server listed in the SPF record for the domain, it is discarded. In this way nobody will be able to mask an email address and make it appear as if you're sending spam messages. This approach is also identified as email spoofing.