Lightning can occur between opposite charges within the thunderstorm cloud (intra-cloud lightning) or between opposite charges in the cloud and on the ground (cloud-to-ground lightning). Lightning is one of the oldest observed natural phenomena on earth.
SYSTEM TESTING Fundamentals. DEFINITION. System Testing is a level of the software testing where a complete and integrated software is tested. The purpose of this test is to evaluate the systemâs compliance with the specified requirements. Definition by ISTQB. 1  system testing: The process of testing an integrated system to verify that it meets specified.
If your test depends on the system, it is a system test, not a unit test. If it depends on code with side-effects, it is an integration test. The simplest unit-test is an isolated test of purely functional code. A more typical example is a test in which the side-effects are mocked. Unit-testing means testing some 'unit' of code, and nothing else. Think of a scientific experiment: The more variables, the less valuable the result of a single run.