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Quality assurance (QA) focuses on measuring and examining the quality of design, development, enhancements and maintenance of processes and products to make sure they conform to requirements, standards, and procedures set forth in a project. Testing, on the other hand, may keep an eye on the processes and often owns them, but is far more concerned looking at ways to break something like systems. Testers are to observe what systems do and to report on the level of quality as well as any serious issues they encounter.
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