In The Groove (Abbreviated to ITG) is a dance game developed by RoXoR and released in 2004.
ITG Began after a group of players saw the market on 4 panel dance games die with the end of Dance Dance Revolution, they developed the game on Debian Linux and a bespoke build of Stepmania. Original artists such as Kyle Ward contributed heavily to the game and some licenses were bought for instance Vanilla Ninja.
It was released into Arcades as an upgrade for older dance machines which caused problems with the new step type Hands which were problematic for the older pads. The quality of the old pads generally made it harder to flat foot as well making high scores harder.
The unique features of ITG meant that edits could be developed for songs via USB (ITG1 had a White list, whilst ITG2 had no limitations other than external powered devices couldn't be used.) Allowing screenshots and more detailed information to be created onto the card.
Alot of the issues with ITG1 were fixed with ITG2 which was co-developed with Andamiro, creators of Pump it up, allowing a custom cabinet to be made (called a Dedicab by fans). This custom cabinet had better pads which allowed flat foot play and hands to be done with ease and making the play alot better for players.
see also ITG court case
On October 18, 2006 it was announced that Konami had won a court case with RoXoR for intellectual property rights, which in effect ended In The Groove. As a final twist to the story, just before the announcement of the result of the court case, RoXoR released a patch for ITG2 which allowed Songs to be played via USB on any machine that had the new R21 patch.
Although some fans of Dance Dance Revolution have a dislike of ITG, it did re-spark interest in the community, with older players coming back to stick in there opinion. Another factor was the fact the game didn't have a formal Japanese release meaning that Japanese players never got a chance to play the game, then again it didn't respond well to tests since it lacked songs that would appeal to their fan base.
ITG home page
 Press release regarding Konami acquiring intellectual rights to ITG.