Ultrasonic testing is a non-destructive testing method that uses high-frequency sound waves to detect flaws in materials. A transducer emits ultrasonic waves, which travel through the material and reflect back when they encounter a boundary, such as a defect or the material's surface. By analyzing these reflections, technicians can identify issues like cracks or voids without damaging the object being tested. This technique is commonly used in various industries, including manufacturing, aerospace, and construction, to ensure the integrity of components. It is effective for testing metals, plastics, and composites, providing accurate results that help maintain safety and quality standards.