SPF, which abbreviates Sender Policy Framework, is a verification system that is aimed at protecting against the so-called email faking. Essentially, this indicates sending a message from one e-mail address and making it look like it’s sent from a different one with the objective to scam in some way the person receiving it. In case the SPF protection is activated for a domain name, a record which contains all of the mail servers authorized to send messages with addresses part of the domain is created. The record is saved on all DNS servers that route the web traffic internationally, thus they all will recognize whether an email message originates from an authentic server or not. The check is done at the very first server where the email goes through and in the first case the message is forwarded, while in the second it's removed and it never reaches its intended recipient. Employing SPF records for your domain names will stop any unauthorized people from making use of your email addresses for malicious objectives.