QA and QC both aim to ensure quality, but they differ in their focus and approach. QA is process-oriented and focuses on defect prevention through planned activities and documentation to improve processes. The goal of QA is to prevent defects. In contrast, QC is product-oriented and focuses on defect identification by testing finished products. The goal of QC is to identify and correct defects after product development. Together, QA and QC work to continually meet customer requirements and product quality standards.