DOCUMENT documentary_text.
DOCUMENT adds one or more lines of descriptive commentary to the active file. Documents added in this way are saved to system files. They can be viewed using SYSFILE INFO or DISPLAY DOCUMENTS. They can be removed from the active file with DROP DOCUMENTS.
Specify the documentary text following the DOCUMENT keyword. You can extend the documentary text over as many lines as necessary. Lines are truncated at 80 characters width. Don't forget to terminate the command with a dot or a blank line.