Business Rules

Here is an attempt:

A Task is something that someone or a system has to perform during a process. It has got input and produces an output. A business rule is evaluated in the course of a task. It may be subject to change frequently, while the task itself remains unchanged.

Example: In a credit application process of a bank there may be the task "Check credit-worthiness". Input will be all sorts of information sources suitable for assessing the credit-worthiness score of a customer. Output will be a decision "Credit risk acceptable" or "Credit risk not acceptable". A business rule executed during that task might say: "If credit-worthiness score is greater than 97% the risk is acceptable, otherwise it is not acceptable." This rule might change frequently depending on the risk the bank is willing to take into the books, while it will remain unchanged, that the credit-worthiness has to be checked. The rule might also change in a way that it takes into account more parameters for the decision. Further business rules might describe how you calculate the credit-worthiness score.

So these concepts serve to separate stable procedures (processes) from unstable business decisions. You might compare it to software development: The task defines the interface (What), while the business rule describes the implementation (How).

Regards, M. Zschuckelt