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3) Assumptions/Pre-conditions: Define what the state of the world is prior to the beginning of the flow of events described in the use case.

4) Post-conditions: Explain what the state of the world will be once the flow of events described in the use case occurs.

5) Business rules: These are the operating rules that govern or constrain the environment in which the process flow happens. For example, “placing an order can only happen between 9AM and 5PM” is a business rule. The use case must obey these rules.

6) Normal process flow: Define the “happy path” for the process flow, step by step and sequentially numbered. The “happy path” essentially means what the default flow is, without accounting for exceptions, conditions, or errors. It should lead to the successful conclusion stated in the post-conditions.

7) Alternate process flows: When there are major decision points or exceptions that create a different path to the conclusion of the use case, then each of those alternate process flows must be defined step by step just like you did with the normal process flow. If you numbered the normal process flow sequentially and the alternate flow begins in a certain step, you can just start the description of the alternate flow from there.

Use Case Wiki template:

Copy and paste into new Wiki page then Edit.

Use Case: Name <Enter Use Case name here>
The use case should be labeled so that it immediately describes the purpose of the use case. Usually, VERB/NOUN is sufficient. 

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