SPF, which is an abbreviation for Sender Policy Framework, is a validation system that aims at blocking the so-called email faking. Basically, it indicates sending some message from one e-mail address and making it look like it’s sent from another one with the purpose to scam in some way the individual receiving it. If the SPF protection is running for a domain, a record that contains all the mail servers authorized to email messages with addresses under the domain is created. The record is placed on all the DNS servers that route the Internet traffic around the world, so they all can identify if an e-mail message comes from a valid server or not. The verification is done at the very first server where the e-mail goes through and in the first case the email message is forwarded, and in the second it is removed and it never gets to its intended recipient. Applying SPF records for your domain names will prevent any unwanted people from using your email addresses for harmful objectives.