The parameters defined on the process definition page can apply to all the scope of the process tasks.
Usage of global parameters is: at the process define page, click the '+' beside the 'Set global' and fill in the key and value to save:
The global_bizdate
parameter defined here can be referenced by local parameters of any other task node, and set the value of global_bizdate
by referencing the system parameter system.biz.date
.