Most attempts at describing the content of binary messages jump immediately into a consideration of the bit codings to be used. A better approach would be to provide a symbolic method for describing messages. The symbolism, by avoiding immediate references to specific bit details, should help one's understanding of the message content and the alternatives available in the message body. When the basic form of the binary message body is clear, the coding details of the actual bit fields can be shown. Describing a binary message body is not much different from describing a text body or language.
Text assumes fixed bit fields each containing one character.
Binary message descriptions require the additional capacity of defining various size fields in the message and the interpretation to be placed on the bits contained in the field. A message description is initially intended as a reference standard to be written down on paper and made available to new users of a computer network. From this standard, the new user can discover the kind and form of the binary data being exchanged over the network. Once this is known, the programs necessary for using the network facilities can be created. Still farther into the future, the text of a binary format standard could be used as input to compiler-like programs which automatically create data translation programs for converting one binary format to another.