This field defines the restriction type:
Restriction
In this case, the restriction is valid for everything that is different from what is registered.
Example:
Suppose restriction was registered for Customer X from 8AM to 6PM on 09/20/03 for the contact Leonardo. The restriction is valid for all the time slots/dates/contacts, except the data registered.
Rule
When the type refers to the rule, the system considers only what is registered in the header and in the item of the restriction.