Quality control is focused on fulfilling quality requirements. It encompasses the operational techniques and activities undertaken within the quality assurance system to verify that the requirements for quality of the product or service have been fulfilled.
Quality assurance, on the other hand, is focused on providing confidence that all aspects of the business operations are controlled. It includes all those planned and systemic actions that are established to ensure quality throughout all the business processes, that data is generated, documented (recorded), and reported to management.
Quality control is generally the responsibility of the operational units and quality is infused into the outputs and verified as they are being generated. Therefore, quality control is an integral part of the daily activities occurring within each operational unit and is only one aspect of quality assurance.