There was this big push in the early 1990s after CD Rom became affordable to make a Jack-of-all-trades machine that could play games, do some sort of computing, play movies, music, your kids can do their homework on it, etc. The CDI was an attempt by Pioneer and Magnavox to try and make a standard "multimedia" device. "CDI" stands for Compact Disc Interactive or something like that. It was a good idea (one that present day consoles are leaning ever closer to) but perhaps in the early 90's the technology just wasn't there.
CDI could play VCD movies with optional MPEG-1 video card (come models have this capability built in,) it could play kind of good looking games, some models even had upgrades that turned it into a somewhat useable computer, but sadly it did none of these things well enough to insure it's success. Pioneer/Magnavox went the VCR route with the machine, making multiple models in multiple price ranges in an attempt to cover all sections of the market. Some machines have the video card built in, some have extra hook-ups for keyboards, disc drives, etc. But the same thing happened to them that happened to the 3DO (and Sega, to some extent,) when you put out two versions of the same machine which are generally within the same price range you end up competing with yourself. Soon all the other models disappeared and the only one left was the el-cheapo 450, which was repackaged and sold as a pure game system. But the arrival of the Playstation, Saturn, and N64 was the death knell for CDI as a viable gaming platform.
The hardware is technically on par with the 3DO (without the 3D capabilities.) What this machine excels in is Full Motion Video, and sadly it seems most of it's games are built around it. Games like Mad Dog MaCree, Dragon's Lair, and Burn Cycle are probably the best this machine has to offer, although there are some surprisingly good games like Mutant League Football. There is sadly an awful lot of boring educational software for this thing like Compton's Interactive Encyclopedia, as well as a lot of stupid kid's games. With the MPEG card it's useful for watching VCDs on your television and there's a few movies that were released in VCD format just for this system (like various Star Trek Movies.) A hard core fan base of CDI users and developers still exist and some software still comes out homebrew style. If a machine like this were to be released today with DVD capabilities and an upgradeable OS and hardware it might do better. Something tells me we haven't seen the last of the "multimedia device."