SPF, which is an abbreviation for Sender Policy Framework, is an authentication system that aims at preventing the so-called email counterfeiting. Basically, this indicates sending some message from one e-mail and making it look like it’s sent from another one with the objective to scam in some manner the person receiving it. If the SPF protection is running for a domain, a record which contains all mail servers authorized to send messages with addresses under the domain is made. The record is stored on all of the DNS servers that route the Internet traffic across the globe, so they all will recognize whether an email message originates from a legitimate server or not. The check is conducted at the first server where the email goes through and in the first case the message is forwarded, but in the second one it is discarded and it never gets to its intended recipient. Employing SPF records for your domain names will stop any unauthorized people from using your emails for malicious objectives.