Test (Test case)

The test case is a specification of the inputs, execution conditions, testing procedure, and expected results that define a single test to be executed to achieve a particular software testing objective, such as to exercise a particular program path or to verify compliance with a specific requirement. Test cases underlie testing that is methodical rather than haphazard. A battery of test cases can be built to produce the desired coverage of the software being tested. Formally defined test cases allow the same tests to be run repeatedly against successive versions of the software, allowing for effective and consistent regression testing.

Google practices the language of the small, medium, and large tests, featuring scope over form, instead of marking between code, integration, and system testing. According to the book How Google Tests Software, we define three types of test

Small test covers a single unit of code in a completely faked environment. (Unit test).
Medium test covers multiple and interacting units of code in a faked environment. (Integration/capability test).
Large test covers any number of units of code in the real integrated environment close to production one with real and not faked resources. (E2E, Smoke, Sanity, Functional, NFR tests)