SPF, which is an abbreviation for Sender Policy Framework, is a validation system that is aimed at stopping the so-called email forging. In simple terms, it indicates sending a message from one e-mail and making it seem to be sent from a different one with the objective to scam in some way the individual getting it. If the SPF protection is active for a domain name, a record which contains all of the mail servers authorized to email messages with addresses under the domain is created. The record is placed on all of the DNS servers that route the web traffic all over the world, so they all can identify whether an e-mail message originates from a legitimate server or not. The check is conducted at the very first server where the e-mail goes through and in the first case the e-mail message is forwarded, but in the second one it is discarded and it never gets to the supposed recipient. Using SPF records for your domain names will prevent any unauthorized people from using your email addresses for harmful objectives.