What is a test oracle used for?

A test oracle is a source used to determine the expected results of a test. It provides a reference against which the actual outcomes of the software under test can be compared. This is essential in testing because, without a clear expectation of what should happen when a particular input is provided, it becomes challenging to assess whether the software operates correctly.

In the context of software testing, oracles can take various forms, such as specifications, user manuals, or even the behavior of previously released versions of the application. Using a test oracle allows testers to identify discrepancies between the expected and actual behavior of the software, thereby helping to pinpoint bugs or issues.

Understanding the purpose of a test oracle emphasizes its critical role in test validation and verification processes, making it a vital concept in both traditional and agile testing environments. The other choices focus on aspects of testing that do not directly relate to the function of an oracle. While creating test cases and managing resources are important activities in testing, they do not define what a test oracle does. Similarly, training team members on test processes is essential for developing skills but is not related to the concept of a test oracle.