Invisible Ink has a long history, though it pales in comparison to that of "colored" ink or other writing systems. It was first invented by Socrates, who alas lost the formula when he wrote a grocery list — "wine, bread, hemlock" — on the seemingly blank sheet of papyrus. The secret to invisible ink disappeared from the records for centuries to come, until it was used by the famed Leonardo da Vinci. Da Vinci used a honey-based invisible ink to write the world's first techno thriller, Frons Code (The Brown Code), which described a futuristic plot to implant implausible secrets in otherwise ordinary religious artwork. After the manuscript was consumed by bees, however, da Vinci gave up his career in fiction writing for the paintbrushes, and invisible ink fell out of favor many years.

It wasn't until the 20th century, when the two World Wars and the rising field of espionage brought invisible ink back to light. The field of steganography — concealed writing — became one of the key tricks of fieldcraft for spies from all countries, fueled in part by the widely available guidebook The Steganosaurus. After World War Two ended and espionage methods came to light, invisible ink finally received due credit and ever since it has been duly commemorated in children's spy kits around the world.