Calypso and Chutney merged to form Soca. The name may have come from "Soul" and "Calypso" but the music itself is clearly derivative from Chutney.
There were two Calypso singers who were highly regarded in their own style and were also able to drop into Soca at will.
Lord Kitchener often based his soca pieces around Pan as in Pan In Harmony.
The Mighty Sparrow combined flexible vocal lines with interesting ideas, as in
Life In Hell.
These days both classic Calypso and Soca can be considered Calypso. Other, later stylistic variations like Rocksteady, Ska, and Reggae, were primarily asociated with Jamaica. Songs in a more Calypsonian or rural style from Jamaica are called Mento.
Later blog entries will have more specific topics, as: variations on a song, or various sings by a particular singer.