Explain path testing.
Path Testing: Testing in which all paths in the program source code are tested at least once. Path testing has been one of the first test methods, and even though it is a typical white box test, it is nowadays also used in black box tests. First, a certain path by the program is chosen. Possible inputs and the correct result are written down. Then the program is implemented by hand, and its result is compared to the predefined. Possible faults have to be written down at once.