Smectic phases are a type of liquid crystal phase characterized by layered structures. In these phases, the molecules are organized in parallel layers, allowing them to slide over one another while maintaining a certain degree of order. This unique arrangement gives smectic phases distinct optical and mechanical properties, making them useful in various applications, including displays and sensors. There are several subtypes of smectic phases, such as smectic A and smectic C, which differ in molecular orientation and layer arrangement. These variations influence the behavior of the liquid crystals, affecting their response to electric fields and temperature changes, which is crucial for their practical uses.