is the cadillac dts and deville the same car if not what is the difference?

DTS became replacement for deville in 06. DTS was the replacement for the concours which replaced the earlier Touring Sedan. Basically it's a STS using a deville body. More HP & Firmer ride,with Night Vision a very cool option. DHS was the replacement for the deElegence - Max Luxury Package, it's was intended to fill the void when the Fleetwoods were terminated after 96.

DTS = Deville Touring Sedan
STS = Seville Touring Sedan
CTS = Catera Touring Sedan