Physical optics is the branch of optics that studies the behavior of light as a wave. It explains phenomena such as interference, diffraction, and polarization, which cannot be fully understood using the simpler ray optics approach. This field helps us understand how light interacts with various materials and how it can be manipulated. In physical optics, light is treated as a wave that can spread out and overlap with other waves. This wave nature of light leads to unique effects, such as the colorful patterns seen in soap bubbles or the way light bends around objects. Understanding these principles is essential for applications in fiber optics and laser technology.