Access 97 – Global Variable

Global Variables – How do I set them up & access the value on several forms

I thought using Global variables was going to be very simple however I am
not sure how to start.

Basically, I want to set a the value of a variable on one form, run areport
with the criteria form closed, then when I close the report have the option
to open another form that would display some criteria data on a form that
was closed a before the report ran.

Is there a way to store data on a form into a variable that can be used
later? I was trying to use a global variable but cannot seem to figure out
how to define one.