Civilization Revolution IV Differences?

What is the difference between civilization 4, civilization 4 warlords %26amp; civilization 4 beyond the sword?

im looking to start a new game and wondering if they were just expansions

i don't know which to start onCivilization Revolution IV Differences?
Civ 4 is the basic game, released on 2005-10-26, the details of which you can view here:



http://www.2kgames.com/civ4/home.htm

http://www.firaxis.com/games/game_detail鈥?/a>



I played it for about one year until the first expansion pack, Warlords, was released on 2006-11-13, which I preordered and played for less than one year. You can observe it here:



http://www.2kgames.com/civ4/warlords/war鈥?/a>

http://www.firaxis.com/games/game_detail鈥?/a>



I also preordered the second expansion pack, Beyond the Sword, which was released 2007-07-23, and I have played that version ever since, for more than a year. It is so much better than Warlords that I strongly recommend it, and Warlords is an unnecessary augment. You can see it here.



http://www.2kgames.com/civ4/beyondtheswo鈥?/a>

http://www.firaxis.com/games/game_detail鈥?/a>



There are no other expansions, and the next version (Civ 5) is probably a year away. Civilization Revolution ( http://www.gamespot.com/xbox360/strategy鈥?/a> ) was released 2008-07-11 for game consoles, and is not available for PC. Civilization IV: Colonization ( http://www.firaxis.com/games/game_detail鈥?/a> ) is the newest version (released 2008-09-22), but it is much simpler than the original Civ 4.