Any parameter that changes with each iteration of a programme should, in general, be regarded as a symbolic parameter. It is possible to get more flexibility in the method by employing symbolic parameters. It won't be necessary to make adjustments to the technique each and every time there is a seemingly little but ongoing change at a certain location. In the case of symbolic parameters, the string of 1 to 7 alphabetic letters is preceded by an ampersand sign (&). After the ampersand (&), you are required to type in a letter from the alphabet. In JCL statements, symbolic parameters are only allowed to appear in the operand field; they are not allowed anywhere else.  JCL statements do not allow symbolic parameters to appear in the name or operation fields. In the event that more than one symbolic parameter is supplied to a PROC or EXEC statement, only the first one will be used.