上游充鱼大姿 SJTU School Of Software 2009-2-3 Demonstrate that software functions appear to be working according to specification. That performance requirements appear to have been met. Data collected during testing provides a good indication of software reliability and some indication of software quality. Testing cannot show the absence of defects,it can only show that software defects are present. 软件学院SJTU School Of Software 2009-2-3 软件学院 Demonstrate that software functions appear to be working according to specification. That performance requirements appear to have been met. Data collected during testing provides a good indication of software reliability and some indication of software quality. Testing cannot show the absence of defects, it can only show that software defects are present