A fluorophore is a molecule that can absorb light at a specific wavelength and then re-emit it at a longer wavelength. This property makes fluorophores useful in various scientific applications, particularly in biological imaging and fluorescence microscopy. They are often used to label specific proteins or cells, allowing researchers to visualize and study biological processes in real-time. Fluorophores can be naturally occurring, like green fluorescent protein (GFP), or synthetic compounds designed for specific applications. Their ability to emit light makes them valuable tools in diagnostics, biotechnology, and pharmaceutical research, helping scientists track and analyze cellular activities.