DMARC is an acronym : Domain-based Message Authentication, Reporting & Conformance
DMARC records are added to the DNS of your domain(s) as TXT records.
They will help improve email deliverability for your domain(s)
All DMARC records have to be in the format of:
and the actual record itself will specify how you want to handle things.
To help generate the DMARC record there are a number of online tools available for guiding you through creating and validating them. See here for a list.
If you specify an email address for reports you will get emails.
If you run into issues please contact our support team