Some IBM-supplied programs allow you to select options from a set of alternatives. The PARM and PARMDD values are listed in the publication for the program. For many IBM-supplied programs, default values can be assigned to the PARM and PARMDD parameters during system initialization. That is, the installation can select an alternative or assign a fixed value. The system uses this default unless you specify another value for the PARM or PARMDD parameter when you execute the IBM-supplied program.
The installation should maintain a list of default values assigned during system initialization.