Halo has become a Revolutionary game that has been produced by Microsoft.  Starting off with Halo 1, Microsoft has also developed Halo 2, Halo 3, and in a month Halo 4.  For those of you who might not know the story behind the original game, it follows the exploits of the Master Chief, a spartan super-soldier.  Being the last of his kind, his task is to defend humanity from the Covenant.  The Covenant is an alliance of alien races who are determined to destroy humanity. You escape to Halo, a mysterious ring-shaped space station of unknown origin with a mission to protect a woman named Cortana, along with the secrets she holds. You must fight Covenant forces while attempting to discover the origins behind Halo.  Also you must discover the reasons behind the structure's creation and existence.  Also it is a lot harder to be more skilled in Halo than Call of Duty.  There are more players in Call of Duty because of how much easier it is.  Halo is exclusive to X Box, while call of duty is on all gaming systems.  Only a true gamer will understand the complexity of Halo.  Halo also was the first game to go online for X Box live.  This step was revolutionary, changing the world of gaming forever.  It allowed players from all over the world to play against each other, instead of having to play split screen with a friend or having to link systems with other X Box's. Halo has set the stage for all shooting games to come.  Halo is extremely tactical in every way of game play.  As hard as it is to learn how to win in one on one combat, another important aspect of the game is in knowing the maps.  A combination of these and many other aspects must be combined to be successful at the game.  Halo is a lot like chess, every move made on the board will affect a move later on, just like every move on the map will affect something later on.  Halo is by far the most tactical shooting game for any gaming system.