It was Atari's hilarious attempt at outdoing the SNES and Genesis and it was marketed as being the first 64 bit console, which was a load of bullsh*t.
Here's a nice little retrospective on it from the nerd.
ScrewAttack Video Game, Angry Video Game Nerd: Atari Jaguar Part I | Game Trailers & Videos | GameTrailers.com
ScrewAttack Video Game, Angry Video Game Nerd: Atari Jaguar Part II | Game Trailers & Videos | GameTrailers.com
Yeah, apparrently the CD add on is so crappy that not even the guy who invented the Nintoaster (a fully functioning NES made out of a toaster) and Super Gentari (an Atari 2600, NES, Genesis and Super Nintendo all rolled into one) can get it to work.