The GFP (Green Fluorescent Protein) exhibits bright green fluorescence when exposed to blue light. Although many other marine organisms have similar green fluorescent proteins, GFP traditionally refers to the protein first isolated from the jellyfish Aequorea victoria. Although it has been used by artists around the world, this GFP is especially useful for the biological sciences. In biology, GFP is used for highlighting specific structures. Compared to other fluorescent proteins, it is much less harmful when illuminated in living cells. The discovery and use of GFP has triggered the development of highly automated live-cell fluorescence microscopy systems, which can be used to observe cells over time expressing one or more proteins tagged with fluorescent proteins. In 2008 Martin Chalfie, Osamu Shimomura, and Roger Y. Tsien were awarded the Nobel Prize in Chemistry for their discovery and development of the green fluorescent protein.
Wiki - Green Fluorescent Protein