SPF, which is an abbreviation for Sender Policy Framework, is a verification system that is aimed at stopping the so-called email faking. Essentially, this indicates sending a message from one email address and making it look like it’s sent from a different one with the objective to scam in some manner the person getting it. If the SPF protection is activated for a domain name, a record that includes all of the mail servers authorized to email messages with addresses part of the domain is generated. The record is kept on all DNS servers that direct the Internet traffic around the world, thus they all can recognize whether an e-mail message originates from a valid 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, and in the second it's discarded and it never gets to the supposed recipient. Using SPF records for your domains will stop any unwanted people from making use of your emails for harmful objectives.