A Quality Assurance Engineer (QA Engineer) is a professional responsible for ensuring that products, especially software, meet specific quality standards before they are released. They design and execute tests to identify any defects or issues, helping to improve the overall user experience. Their work often involves collaborating with developers and product managers to understand requirements and provide feedback. QA Engineers use various testing methods, including manual testing and automated testing, to evaluate functionality, performance, and security. They document their findings and work to resolve any problems, ensuring that the final product is reliable and meets customer expectations.