1 The Pattern Languages of Programs conference.

2 Technically, they are not truly patterns until they have been discovered by three independent project teams.

3 The testing function is sometimes referred to as "Quality Assurance." This usage is, strictly speaking, incorrect.

4 The Law of Raspberry Jam: "The wider you spread it, the thinner it gets."


1 A small percentage of the unit tests may correspond directly to the business logic described in the requirements and the customer tests, but a large majority tests the code that surrounds the business logic.

2 A change in behavior could occur because the system is doing something different or because it is doing the same thing with different timing or sequencing.

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