1. The process of testing an integrated hardware and software system to verify that the system meets its specified requirements. Such testing may be conducted in both the development environment and the target environment.

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The process of testing an integrated hardware and software system to verify that the system meets its specified requirements.

2. Final stage of the testing process should be System Testing. This type of test involves examination of the whole computer system. All the software components, all the hardware components and any interfaces.

The whole computer based system is checked not only for validity but also for met objectives.

It should include recovery testing, security testing, stress testing and performance testing.

Recovery testing uses test cases designed to examine how easily and completely the system can recover from a disaster (power shut down, blown circuit, disk crash, interface failure, insufficient memory, etc.). It is desirable to have a system capable of recovering quickly and with minimal human intervention. It should also have a log of activities happening before the crash (these should be part of daily operations) and a log of messages during the failure (if possible) and upon re-start.

Security testing involves testing the system in order to make sure that unauthorized personnel or other systems cannot gain access to the system and information or resources within it. Programs that check for access to the system via passwords are tested along with any organizational security procedures established.

Stress testing encompasses creating unusual loads on the system in attempts to brake it. System is monitored for performance loss and susceptibility to crashing during the load times. If it does crash as a result of high load, it provides for just one more recovery test.

Performance testing involves monitoring and recording the performance levels during regular and low and high stress loads. It tests the amount of resource usage under the just described conditions and serves as basis for making a forecast of additional resources needed (if any) in the future. It is important to note that performance objectives should have been developed during the planning stage and performance testing is to assure that these objectives are being met. However, these tests may be run in initial stages of production to compare the actual usage to the forecasted figures.

3. System testing is black box testing, performed by the Test Team, and at the start of the system testing the complete system is configured in a controlled environment.

The purpose of system testing is to validate an application's accuracy and completeness in performing the functions as designed.

System testing simulates real life scenarios that occur in a "simulated real life" test environment and test all functions of the system that are required in real life.

System testing is deemed complete when actual results and expected results are either in line or differences are explainable or acceptable, based on client input.

Upon completion of integration testing, system testing is started. Before system testing, all unit and integration test results are reviewed by Software QA to ensure all problems have been resolved. For a higher level of testing it is important to understand unresolved problems that originate at unit and integration test levels.