Rule Components

Rules are created from a combination of the following basic components:

Condition	A condition is a high-level logical test that defines the syntax for a rule or action. It defines the sequence in which tests are performed.
Relationship	A relationship compares any two values and returns a result of true or false.
Value	A value is a constant, a reference to objects or a calculation.

Components are structured in a hierarchy of nodes (see Parent and Child Nodes) which determines the sequence in which each condition is tested.

Most conditions are tested one after the other, from the top of the rule to the bottom. The exception is "IF...THEN...ELSE", where either one condition is tested or another, depending on an initial test.