Nonclassical light refers to light that exhibits properties beyond those of classical electromagnetic waves. Unlike traditional light, which can be described by classical physics, nonclassical light often involves quantum phenomena, such as entanglement and squeezing. This type of light can be generated using special techniques and is essential for advanced applications in quantum optics and quantum information. One of the most notable examples of nonclassical light is squeezed light, which has reduced uncertainty in one property, like phase or amplitude, while increasing it in another. This unique characteristic makes nonclassical light valuable for improving the sensitivity of measurements in quantum computing and quantum communication technologies.