Dye Penetrant Testing is a non-destructive testing method used to identify surface defects in materials. It involves applying a liquid dye to the surface of the object being tested. After a set period, the excess dye is removed, and a developer is applied, which draws the dye out of any cracks or flaws, making them visible. This technique is commonly used in industries such as aerospace, automotive, and manufacturing to ensure the integrity of components. It is effective for detecting surface-breaking defects like cracks, porosity, and laps, helping to maintain safety and quality standards.