At the process level, you have the option of defining variables that can be set to (filled with) various possible values throughout the iterations as the simulation is run. The variables defined here reflect the variables defined and used in the actual process, but are only applied during simulation.
Define all simulation variables at the process (pool) level (ie globally) and then assign and configure them in tasks if you need local variable there (for example to define a Boolean yes or no to take one path or another, based on a previous decision taken in the process case).
Three types of data can be defined in simulation iterations: