Bud, I think your qestion is a somewhat regional thing, or perhaps a North/South thing. Most people here call it soda but certainly know what your talking about if you call it pop. I just looked on the web, there are actually debate type pages set up about this very subject. Who knew.
Soda
...anyone call it "pop"?
I was in D.C. once and walked up to a street vendor and ask what kind of pop do you have?
After no response and a strange look I ask if they sold pop? Another strange look and no response,
so again I ask, do you sell pop? Nothing but awkward stares. I never got my pop and it only took me
a couple of years to find out why. My aunt, from Maryland, explained to me they call it soda. I thought
soda was ice cream and pop. (That's a float.)