Testing

format test cases are procedures used to test object oriented classes using the ASTOOT methodology. (google it) In a nutshell, a format test case excerscises the functionality of an object and helps to identify any code defects within that the class. (an object being the instantiation of a class for this purpose)
A use case is how an object is used. an elevator is an object. two use cases are a user goes up, and a user goes down.
(sevirty is not a word) severity is used to classify bugs with regards to how severe their effects are. a bug with low severity might be a misspelled word on a label while a severe bug would blow away accumulated work. (priverty is not a word) Priority would be how important a bug is. of course the most severe bugs arer the highest priority so priority only comes in for bugs of the same severity. for example a misspelled title would have a higher priority than a misspelled word in the text.
if you truly do mean sevirty and priverty please feed me back their usage in context.

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