I know I specified DDR Extreme as the next episode for Dance Dance Retrospective, but before we can go into that, we have to get something else out of the way first. Extreme features song crossovers from every series from the Bemani franchise, the catch-all trademark for Konami's music games, up to that point. Therefore we should take a moment to examine and understand all these games, and what kind of music (if any) they specialise in. NB: Very few Bemani games outside of Dance Dance Revolution have had official releases outside of Japan, so expect disappointment if you should become inspired enough to look for one of them at your local arcades. Furthermore, all game counts refer to arcade releases unless otherwise noted.
Beatmania (1997-2002, 13 games)
The first Bemani series was a DJ simulation game, utilising a 5 button keyboard and a turntable. While earlier games did have more of a focus on hip-hop, hence the turntable, the range of genres present throughout the Beatmania games is extremely eclectic; so much that genres are listed along with song titles. The last game, beatmania The Final, was released in Japan in July 2002.
Beatmania IIDX (1999-Present, 19 games)
Pronounced "2-D-X", this spinoff of Beatmania added two keys to the control setup, and for some reason overtook the original series in popularity. The latest game, beatmania IIDX 19: Lincle, was released in Japan in September 2011. It also got an American release, simply titled beatmania (PlayStation 2, March 2006) (read my review here), which sadly failed to gain much attention in the post-Guitar Hero market.
Beatmania III (2000-2002, 5 games)
A short-lived offshoot of Beatmania which used the 5-key-and-turntable controller from the original series, plus a bass pedal (think Rock Band's drum set). The last game, beatmania III The Final, was released in Japan in July 2002.
Dance Dance Revolution (1998-Present, 14 games)
If you don't know what this is, you need to start over. The latest arcade game, DanceDanceRevolution X2, was released worldwide in June 2010, with DanceDanceRevolution X3 vs. 2ndMIX currently in development. The latest home game, DanceDanceRevolution II, was released for Wii in North America in October 2011.
Dance Dance Revolution Solo (1999-2000, 3 games)
Sometimes counted as its own series. Read more here. The latest game, Dance Dance Revolution Solo 4thMIX Plus, was released in Japan in December 2000.
Guitar Freaks & DrumMania (1998-Present, 19 games)
A sort of precursor to the Guitar Hero/Rock Band dynasties. Guitar Freaks uses a guitar controller with 3 fret buttons, and DrumMania uses a drum kit with 5 pads and a bass pedal. Both Guitar Freaks and DrumMania arcade games run on separate cabinets, but can be linked to play together. The latest game in the core series, Guitar Freaks & DrumMania V8, was released in Japan in March 2011.
Guitar Freaks & DrumMania XG (2010-Present, 2 games)
Basically the original GF & DM on steroids. The GF guitar now has 5 fret buttons, and the DM drum kit has 7 pads and 2 bass pedals. The latest game, Guitar Freaks & DrumMania XG2: Groove To Live was released in Japan in March 2011.
KeyboardMania (2000-2001, 3 games)
The KeyboardMania series uses a 2-octave piano keyboard, similar to the one we got with Rock Band 3. KeyboardMania machines can also link up and play simultaneously with some versions of Guitar Freaks & DrumMania. The last game, KeyboardMania 3rdMIX, was released in Japan in Winter 2001.
Pop'n Music (1998-Present, 19 games)
Pop'n Music has been described by some as a cuter beatmania. This description, while an oversimplication, is surprisingly apt. Like in IIDX, when Pop'n Music goes hard, it gets really intense. The controller uses 9 large, coloured buttons (an "easier" 5-button mode is also available). The latest game, Pop'n Music 19: Tune Street was released in Japan in December 2010, with Pop'n Music 20: Fantasia currently in development.
Dance ManiaX (1999-2001, 3 games)
A different type of dance game, to play Dance ManiaX (spelled differently from Dancemania), you wave your hands over or under a set of four motion sensors. This is one of the few Bemani series (to date) that has never had any home console releases. The last game, Dance ManiaX 2ndMIX Append JPARADISE, was released in Japan in 2001.
ParaPara Paradise (2000, 2 games)
This is similar to Dance ManiaX, in that you wave your hands over five floor-mounted motion sensors arranged in a semi-circle in front of you. It was designed to tie into the para-para dance craze (think "Hare Hare Yukai"), and indeed some of the charts mimic the actual dance routines for their respective songs. The last game, ParaPara Paradise 2ndMIX, was released in Japan in 2000.
Mambo a Go Go (1 game)
While Mambo a Go Go was not technically released under the Bemani brand, it did have a few songs used in DDR Extreme. It uses 3 conga drums which can be hit in 3 different zones each, so it plays somewhat like Namco's Taiko Drum Master series, but with Latin music.
From here on out, the Bemani series you're about to read... about did not exist prior to DDR Extreme, but hey, I strive for completion.
Jubeat (2008-Present, 4 games)
Pronounced "you-beat", with a German 'J'. Unlike most other Bemani games, Jubeat doesn't try to invoke playing a particular instrument; you tap a grid of 16 buttons, each with a mini-screen behind them, and you must press buttons when a marker grows to a certain point, in time with the music. The latest game, jubeat Copious, was released in Japan in September 2011. The latest home game, jubeat Plus (Japan, 2010) / jukebeat (USA, 2011), is also available for the iPad.
Reflec Beat (2010-Present, 1 game)
Reflec Beat uses a large touchscreen, on which you must hit moving notes when they cross a line, and is (a bit too) similar to the rival DJMAX Technica series. The latest game, Reflec Beat, was released in Japan in September 2010, with Reflec Beat LIMELIGHT currently in development.
Dance Masters (2010-Present, 1 game)
Unlike all the other Bemani series, the first Dance Masters (known as Dance Evolution outside North America) game was released for the XBox 360, and uses the Kinect camera system. It is a full-body dancing game much like its rival series, EA/Harmonix's Dance Central, but eschews Euro-American pop for Konami original songs used in DDR and other series. An arcade port for Japan is currently in development.