Can you explain what is meant by a test case that confirms the correct operation of the system?

A test case that confirms the correct operation of the system is a set of input data, conditions, and expected results that verify the system performs its function according to the requirements. Such a test case typically includes:

• Clearly defined input parameters.
• Expected result or behavior.
• Steps to reproduce.

For example, for a method that calculates the sum of two numbers, a test case might look like this:

@Test
public void testSum() {
    int result = Calculator.sum(2, 3);
    assertEquals(5, result);
}

If the test passes, it means the system works correctly for this scenario.