Basic definitions (1)
Command (C): whole word (text string), abbreviation, or string of words representing actions requested of the system.
Argument (A): independent variable (including object) used in a command phrase to modify or direct the action of a command (NOTE: arguments often include parameters).
Command language (CL): command set(s), phrases, structure and syntax associated with a specific interaction of a user with a system by means of commands.
Command language structure: logical structure of the command dialogue (and associated phrases).
Command phrase: phrase including the command (words or their abbreviations) and associated separators and arguments (with parameters).
Command set: all available commands to the user to perform a given task in a particular application context.
Command syntax: sequential and other procedural requirements for inputting the components into command phrases.