"Code" can be defined as (verb) to write computer programming, or [biochemistry] to define a genetic sequence. "Code" comes from the Latin "codex" first used as a descriptor by the first-century AD Roman poet named Martial*.
The Latin "codex" is from the Latin "caudex" meaning the trunk of a tree. Codices were the term for blocks of hand-written sheets of bound papyrus, vellum, or paper. Alternative forms of a codex include a continuous scroll parchment and a folded concertina.
The Mayans wrote on folded codices of bark cloth, using their language's written numerals in a regulated system of layered bars and dots^. The Mayans used a bar to represent five (5) and a dot to represent one (1) and a standardized icon` representing a shell to stand for zero (0).
* "Martial" (adjective) meaning appropriate to war, from the Latin "Mars" for the Roman god of war and agriculture, as most wars are fought over resources, namely staples of survival, e.g. food.
^ Morse code transmits a text kinetically via visual blinks and flashes or an audio set of clicks or tones, but is written in static as bars and dots.
` "Icon" is known to have first been used as a computing term in 1982. The individual digits of 1982 can be added as: 1+9 = 10 = 1+0 = 1+8 = 9 + 2 = 11 = 1+1 = 2 = two layered bars in the written Mayan numeral language, which is also the symbolic icon of an "equals sign," i.e. =.