G.I. Joe: Sigma 6 is a line of military-themed action figures and toys that appeared in the fall of 2005. The toyline is produced by Hasbro and continues the theme and characters established by G.I. Joe: A Real American Hero. It is also an animated series produced by the Japanese animation studio GONZO, currently airing on 4Kids TV and G4, and will start airing on YTV in the fall of 2006. It will consist of 26 episodes. It also has a 6-issue comic series published by Devil's Due Productions.
The Sigma 6 toyline served Hasbro several purposes. First, it allowed them to depart from the classic 3 ¾-inch format of the A Real American Hero series. All Sigma 6 action figures stand at approximately 8 inches and have more articulation. Second, the new series offered them the chance to streamline the storyline and characters for a new younger audience. It is hoped that Sigma 6 would follow in the success Hasbro had with Transformers: Armada and their hope is a multimedia revival of G.I. Joe. To accomplish this task, much of the old continuity has been stripped away leaving younger versions of icons from the past. (Wikipedia)