Lecture 10
Purposes of Testing
1. Verification and Validation
o Verification: Ensures the software meets specified requirements.
o Validation: Confirms the software meets the customer’s needs.
o Two Main Goals:
Demonstrating the software meets its requirements.
Discovering faults or defects that cause the software to
deviate from its specifications.
2. Types of Testing Outcomes
o Successful Test: The system performs as expected under the test
conditions.
o Failure Discovery: The test exposes a defect or undesirable
behaviour.
Traditional Testing in Large Systems
1. Testing Phases
o Unit Testing: Testing individual components or modules.
o Sub-System Testing: Testing integrated components.
o System Testing: Testing the complete system.
o Acceptance Testing: Testing the system in its operational
environment.
2. Verification and Validation in Testing
o Each testing phase contributes to both verification (ensuring the
system is built right) and validation (ensuring the right system is
built).