Positive tests cases are cases that go along with the scenario. Negative test cases are any case that deviate from that scenario.
So some examples are:
- Positive
- Man jumps from building's top to the ground
- Man flies from the building's top to the Moon and flies back to the bottom
- Or any way that guarantees that the man starts from the building's top to the bottom
- Negative
- Man jumps from building's top to the ground but the gravity suddenly becomes negative and he cannot touch the ground
- Same like above, but the wind upward is too strong
- Same like above, but something prohibits him to go further when he is
X% (0 <= X <= 100) done with his journey
- Any deviation from any positive test case is a negative test case.
I use the notion X to mean that it is one of the examples where the number of test cases are infinite.
My experience so far explaining testing to people is that people in the IT industry don't understand enough about testing yet. In this example I try to explain how abstract testing is, but not sure if it is well perceived and understood.