Frequency rules are a set of rules used to define the number of times a contact should be contacted by any means in Mautic. At this stage Email and SMS have been implemented, but other forms of contact should also be applied as necessary. Such as social media mentions or messages sent in the future.
Frequency rules can be set globally from the configuration panel on both the email and sms settings.
Frequency rules can also be applied on a contact's detail page, from the dropdown menu on the upper right hand side. In this area you can select the channels where you want the rules to apply. Setting the rule here will override the general settings.