What is the importance of testing and quality assurance?
QA tends to be focused on measuring and examining quality and improving the software through process improvements, thereby guiding the release to customers. Although testing activities usually do take place in this organization, the main focus of QA is on the processes and procedures of how software development activities take place.
Testing, on the other hand, may keep an eye on the processes and often owns them, but is far more concerned with finding ways to break the software. Testers are to observe what the software does and to report on the level of quality as well as any serious issues they encounter.