Cryptography, or cryptology, is the practice and study of techniques for secure communication in the presence of adversarial behavior. More generally, cryptography is about constructing and analyzing protocols that prevent third parties or the public from reading private messages. Modern cryptography exists at the intersection of the disciplines of mathematics, computer science, information security, electrical engineering, digital signal processing, physics, and others. Core concepts related to information security are also central to cryptography. Practical applications of cryptography include electronic commerce, chip-based payment cards, digital currencies, computer passwords, and military communications.

"The Gold-Bug" is a short story by American writer Edgar Allan Poe published in 1843. The plot follows William Legrand, who becomes fixated on an unusual gold-colored bug he has discovered. His servant Jupiter fears that Legrand is going insane and goes to Legrand's friend, an unnamed narrator, who agrees to visit his old friend. Legrand pulls the other two into an adventure after deciphering a secret message that will lead to a buried treasure.