To me, Reggae covers a number of styles.
Ska, Dubwise and Rocksteady ~ roots reggae and dancehall reggae.
Then there is the Rastafari Reggae, my personal favourite.

Calypso is a very different Musical genre, different rhythms
involved but I really enjoy dancing to Calypso. Notting Hill Carnival in London was a yearly event I had to attend to dance my feet off !
I am not too into dancehall Reggae but listen to a lot of Ska and Dub and Rasta Reggae and I have a pretty big collection of Reggae Music dating way back to it's roots with a lot of early Rasta Reggae in there.. Roots~ Rock~ Reggae~ fresh *smile*
That how 'I' overstands it anyway.
Sorry I am not able to get academic about the differences between these two types of wonderful Music but I sure can tell the difference when I hear them...(and so can my feet *grin*)

Ire
Jude