Black box testers usually write test cases for the majority of their testing activities. A test case is usually a single step, and its expected result, along with various additional pieces of information. It can occasionally be a series of steps but with one expected result or expected outcome. The optional fields are a test case ID, test step or order of execution number, related requirement(s), depth, test category, author, and check boxes for whether the test is automatable and has been automated. Larger test cases may also contain prerequisite states or steps, and descriptions. A test case should also contain a place for the actual result. These steps can be stored in a word processor document, spreadsheet, database or other common repository. In a database system, you may also be able to see past test results and who generated the results and the system configuration used to generate those results. These past results would usually be stored in a separate table.
The most common term for a collection of test cases is a test suite. The test suite often also contains more detailed instructions or goals for each collection of test cases. It definitely contains a section where the tester identifies the system configuration used during testing. A group of test cases may also contain prerequisite states or steps, and descriptions of the following tests.
Collections of test cases are sometimes incorrectly termed a test plan. They may also be called a test script, or even a test scenario.
Most white box tester write and use test scripts in unit, system, and regression testing. Test scripts should be written for modules with the highest risk of failure and the highest impact if the risk becomes an issue. Most companies that use automated testing will call the code that is used their test scripts.
A scenario test is a test based on a hypothetical story used to help a person think through a complex problem or system. They can be as simple as a diagram for a testing environment or they could be a description written in prose. The ideal scenario test has five key characteristics. It is (a) a story that is (b) motivating, (c) credible, (d) complex, and (e) easy to evaluate. They are usually different from test cases in that test cases are single steps and scenarios cover a number of steps. Test suites and scenarios can be used in concert for complete system tests.
Scenario testing is similar to, but not the same as session-based testing, which is more closely related to exploratory testing, but the two concepts can be used in conjunction.