Meaning – The term message, refers to an assembly of characters and sometimes control codes that are transferred as an entity from an originator to one or more recipients. A message consists of two parts: envelope and content.
In VTAM, the amount of function management data (FMD) transferred to VTAM by the application program with one SEND request.
There are two main senses of the word “message” in computing: messages between the human users of computer systems that are delivered by those computer systems, and messages passed between programs or between components of a single program, for their own purposes.
Example of usage – “Instant messaging and emails are examples of computer software designed for delivering human-readable messages in formatted or unformatted text, from one person to another.”