Software systems are an integral part of life, from business applications (e.g., banking) to consumer products (e.g., cars). Most people have had an experience with software that did not work as expected. Software that does not work correctly can lead to many problems, including loss of money, time, or business reputation, and even injury or death. Software testing is a way to assess the quality of the software and to reduce the risk of software failure in operation. A common misperception of testing is that it only consists of running tests, i.e., executing the software and checking the results. As described in section 1.4, software testing is a process which includes many different activities; test execution (including checking of results) is only one of these activities. The test process also includes activities such as test planning, analyzing, designing, and implementing tests, reporting test progress and results, and evaluating the quality of a test object.
Testing and debugging are different. Executing tests can show failures that are caused by defects in the software. Debugging is the development activity that finds, analyzes, and fixes such defects. Subsequent confirmation testing checks whether the fixes resolved the defects. In some cases, testers are responsible for the initial test and the final confirmation test, while developers do the debugging, associated component and component integration testing (continues integration). However, in Agile development and in some other software development lifecycles, testers may be involved in debugging and component testing.
