general meaning

to convert or translate. to convert (a message, information, etc.) into code.

Code(in this context):

  1. a system for communication by telegraph, heliograph, etc., in which long and short sounds, light flashes, etc., are used to symbolize the content of a message: e.g.Morse code.
  2. a system used for brevity or secrecy of communication, in which arbitrarily chosen words, letters, or symbols are assigned definite meanings.