IBM's job control language -- the shell of the mainframe.
Designed for easy processing from punch cards of the OS360 system.
Significant source of
LegacyProblems?.
The reference guide [1] and the user's guide [2] are on line available.
Quote of the year on page 25 of the user's guide,
Chez MVS
--ArieVanDeursen &&
TobiasKuipers