There seems to be two different types of Hibiscus, Hardy or Tropical, but I don't see any place in the database for that?

There are not terms that are applied to all hibiscus, but used in conjunction with two specific groups of hibiscus. Although Tropical could be applied to any hibiscus that comes from the tropical, but is usually only used in reference to Hibiscus rosa-sinensis. Hardy could be applied to several of Hibiscus section Muenchhusia it's usually used to describe Hibiscus moscheutos.
If you type in Tropical Hibiscus into the database search you will get this page. http://garden.org/plants/searc...
A Hardy Hibiscus search will get this. http://garden.org/plants/searc...

A little knowledge is a dangerous thing...This article has me confused. Being new to actually learning anything about Hibiscus (I have grown some for many years without even knowing what they were). I took it to mean there were just two kinds of Hibiscus...Thanks. I think I understand what you're saying.

When someone says they grow Tropical Hibiscus they almost always mean Hibiscus rosa-sinensis. When they say Hardy Hibiscus, it's almost always Hibiscus moscheutos. There are many other Hibiscus that are "tropical" or "hardy" but they generally are not referred to by those terms. Did you know that you at least eight species of Hibiscus that grow wild in Alabama? Five of these are native to your state. The native variety are Hibiscus aculeatus, Hibiscus coccineus, Hibiscus grandiflorus, Hibiscus laevis, Hibiscus moscheutos. The non-native species are Hibiscus mutabilis, Hibiscus syriacus, Hibiscus trionum.