DMARC is an email authentication protocol that stands for “Domain-based Message Authentication, Reporting, and Conformance”. DMARC is designed to give email senders and receivers a way to verify that an email is truly from the domain it claims to be from, and to prevent spoofing and phishing attacks. DMARC works by verifying the alignment of the “From” address in an email with the sender’s actual domain. If the two don’t match, the email fails DMARC authentication. DMARC also provides a way for receive domains to report back to the sender about any emails that failed DMARC authentication, so that the sender can take action to fix the problem. DMARC is just one of several email authentication protocols, but it is by far the most widely used. Most major email providers support DMARC, and many require DMARC authentication for emails sent from their domains.