Test Cases are the ”building blocks” (keywords) for testing. They can:
contain other (referenced) Test Cases (Section 3.9.2, “Adding items to editors”)
contain Test Steps (Section 3.16.1, “Specifying Test Steps”)
be used in Test Suites (Section 3.9.2, “Adding items to editors”)
be used as Event Handlers (Section 3.26, “Dealing with errors in tests: Event Handlers”)