What is a Command Language (CL)
CL were used by many early computers and they remain very common.
CL may however suffer from un-meaningful names.
CL has usually a prompt (e.g. c:\>) to tell the user where to type in the commands.
CL requires commands to expressed using a precise syntax, and associated parameters, and are intolerant of even the slightest syntactic errors.
The initiative of navigation is on the user who has to know what the allowable commands are and to have a clear idea of the function.
CL is clearly unsatisfactory for novice users, but for the expert it typically represents the quickest form of communication, especially where abbreviations for commands names are allowed (e.g. <ctrl> <s> to save a file).