On several occasions T-ara formed sub-groups (or sub-units). These were smaller girl groups formed with a few members of T-ara. The first sub-groups of T-ara were formed in March 2013 when "Bunny Style!" was released. These made a few of the songs that were included with "Bunny Style!" in special editions. As these groups had no activity apart from T-ara, they had no official names. The first official sub-groups came a few months later.