Glossary
SPF (SPF)
An email setting that lists which servers are allowed to send mail for your domain, helping prove your emails are really from you.
SPF stands for Sender Policy Framework, but you do not need the full name to use it. In plain terms, SPF is a setting that lists which servers are allowed to send email on behalf of your domain.
When your email arrives, the receiving mail provider can check that list. If the message came from an approved server, that is a point in your favor. If it came from somewhere not on the list, that looks like someone pretending to be you, which is exactly what spammers and scammers do.
Email arrives -> Provider checks: is this server on the approved list?
Yes = looks legitimate
No = looks like spoofing
Why this matters for making money online: if you send a newsletter or promotions and your email is not properly set up, providers are more likely to send it to spam or block it. An email nobody sees earns nothing. Good setup helps your mail reach the inbox.
SPF is one of three settings that work together. SPF says who is allowed to send, DKIM proves the message was not tampered with, and DMARC ties them together and tells providers what to do when a check fails. You want all three.
The good news is you usually do not configure this by hand. Your email service provider gives you the exact records to add. To see how email turns into revenue, read how email marketing makes money.