A class groups a collection of rules or other objects. Each class defines capabilities (rules that include properties, activities, and HTML forms) that are available to other subordinate classes or to instances of the class. Classes are organized into a hierarchy, where the system searches the class hierarchy from the current class upward when looking for a rule to apply. A class is an instance of the Rule-Obj-Class rule type.

A property defines the format and visual presentation of data in your application. Each property can be associated with a value and has a mode and type. The property mode, such as Single Value or Page List, defines the structure that is used to store the property value. The property type, such as Text or Date, defines the format and allowable characters in the property value.