cv-joint etc

O.K. Not really a newb to all this, just been out of the game for a while. 's members have come a long way in mods since I left.
Anyway, people mention cv-joints a lot when talikng about the replacement of the rear shaft with a front and a SYE. I was just wondering if when saying "CV-Joint" you all mean Double Cardan or a true CV? The reason I ask is, I was always taught that a true CV was inferior to a DC. Yes/No?
Thanks

For the driveshaft, they are talking about a Double Cardan joint.

Some of the newer jeeps actually have a constant velocity joint on the driveline(s)

But in this case we are talking about a DC.