Uppercase/lowercase notation

Uppercase and lowercase letters in commands are not distinguished, with the exception of operand values where the distinction is relevant for command execution. For instance, the uppercase and lowercase letters in the WRITE-TEXT command from the sample procedure given above are output as entered. Within this manual, however, commands are represented using mostly uppercase letters, as this is the traditional notation that is supported by all editors, terminals and output devices.

Where lowercase letters are used in command definitions, they often represent variable parts that have to be replaced by suitable current values (see the description of the metasyntax as of "SDF syntax representation ").