RP-IMP-C2-B2 macro in HR ABAP?

Hi Experts,

I am new to HR ABAP programming.I got a requirement  to modify existing  customized program.In that customized program ,RP-IMP-C2-B2 macro is called ,and this one is returning ZES internal table.This intenal table is used in the program.Kindly anyone advise what is the use of this ZES internal table,how this internal table is getting populated.

Thanks in advance,

Anusha.B