Fluorescent dye is a type of chemical compound that emits light when exposed to specific wavelengths of light, usually ultraviolet (UV) light. These dyes are commonly used in various applications, including biological research, where they help visualize cells and tissues under a microscope. The emitted light can be seen in vibrant colors, making it easier to identify and study different structures. In addition to research, fluorescent dyes are also used in industries such as textiles, forensics, and biotechnology. They can help trace leaks in pipes, enhance the visibility of certain materials, and even mark items for security purposes. Their unique properties make them valuable tools in both scientific and practical applications.