Parvisipalum,cochlopetalum, ect. What do they mean?

[The Orchid Boy]

In learning about paphs I have heard the terms parvisepalum and cochlopetalum and others similar. I know that these somehow classify paphs but I don't understand it all yet.

I know that Paph. delenatii is in the parvisepalum group and Paph. moquettianum is in the cochlopetalum group.

What do these mean and how do you know which paphs belong to which group?
What are all the similar terms to classify paphs?

---------- Post added at 04:03 PM ---------- Previous post was at 03:54 PM ----------

Ok I found this site: Phils Orchid World, Pasphiopedilum species, sections and culture
These subgenuses(?) are what I'm talking about:
PARVISEPALUM
BRACHYPETALUM
POLYANTHA
SIGMATOPETALUM
COCHLOPETALUM

So are these just subgenuses used by scientists to classify orchids? How important is it that you know them? Are these all the subgenuses for paphs?