Each type of variable requires a unique prefix to reference it.
Type  | Prefix  | Example  | 
|---|---|---|
Global  | $  | %$SomeGlobalVariable%  | 
Rule Set  | #  | %#SomeRuleSetVariable%  | 
Temporary  | @  | %@SomeTemporaryVariable%  | 
In most cases the reference is generated for you automatically. For example, if you assign a temporary variable named JobName directly to an action parameter, the selected variable name is converted to a variable reference string of the form %@JobName%.
 Variable references can also be used as part of expressions. To increment the value of a Rule Set variable named UsageCount, the value is the expression 1 + %#UsageCount%. This expression is evaluated at runtime and the result assigned back to UsageCount.

