(Pressman 1988) Electric Jeopardy!
A traditional box game packaged with a crude battery-operated lock-out device.
    (Tiger 1995) Jeopardy! Electronic LCD handheld game
This original version also featured additional cartridges (as many as a dozen) sold separately.  Each cartridge (including the one that came with the game) contained 30 categories and over a thousand clues, and also included a separate Answer/Question Book.  Because the main unit used category numbers rather than category names, each cartridge could feature thirty different categories.  This original game was released in two different packages, but the game and the material were identical in both.  The travel versions and deluxe edition below are entirely different games.
    (Tiger 1998) Travel Jeopardy!
A smaller version of the original above.  Each of the three travel versions (released simultaneously to the market) featured its own Answer/Question Book and 500 clues but no LCD screen.  The travel versions were completely self-contained and not expandable.
    (Tiger 1999) Deluxe Edition Jeopardy!
A "new and improved" version of the 1995 game featuring 60 categories and 1500 clues.  This new version showed the clues on its LCD display, eliminating the need for a separate Answer/Question Book.  Two additional cartridges, each featuring 60 different categories and a thousand new clues, were sold separately.
    (Tiger 2002) Jeopardy! Remote
A hand-held unit with three detachable wireless remote signalling devices.
    (Tiger 2002) Jeopardy! Pocket Game
A tiny hand-held unit with 60 categories and 600 clues.
    (Tiger 2002) Jeopardy! Classic
A slightly smaller and slightly revamped version of the Deluxe Edition, with 60 new categories and 1200 clues, but no expansion cartridges.
    (Educational Insights 2002) Classroom Jeopardy
An elaborate, officially licensed educational tool that lets a teacher use pre-programmed game cartridges aimed at elementary and middle school students or create original material.  A variety of game cartridges for the unit are sold separately.
    (Jakks Pacific 2007)
The Jakks 'plug-and-play' version attaches directly to your television set via standard video and audio cables.