Depending on the size of the SUT and the scenario in which it is exercised, testing can be carried out at different levels. In this book, we classify the different testing levels in four phases:
- Unit testing: Here, individual program units are tested. Unit testing should focus on the functionality of objects or methods.
- Integration testing: Here, units are combined to create composite components. Integration testing should focus on testing components, interfaces.
- System testing: Here, all of the components are integrated and the system is tested as a whole.
- Acceptance testing: Here, consumers decide whether or not the system is ready to be deployed in the consumer environment. It can be seen as a high-level functional testing ...