" Encrypted digital watermarking,” explains Balthazar. “Information gets hidden in information, like a code inside the pixels. Only visible with the right kind of key. It’s called steganography. Here,” pointing at the cylinder, “they’re using a similar technique, but done at the nano-level, with DNA as the information carrier. GFP is green fluorescent protein, in this case jellyfish genes woven into the atoms of the metal. The heat from your hand is the key. "
― Steven Kotler , Last Tango in Cyberspace