Civilization I is a turn-based strategy game that begins at 4000 BC in a world containing up to seven civilizations are spread across the lands, each starting with next to nothing. You can choose from five different skill levels and select your tribe from over 9 different civilizations, each with their own points of differences and advatanges. You will be involved with a battle to conquer the globe and along the way, you must deal with balancing your economy, maintaining civil order, and keeping your population fed. Throughout the game you will engage in war, develop diplomatic and trade relationships with other civilizations, and eventually send a spaceship to Alpha Centauri.
The beauty of the game is that there are no set paths a player is forced to take and you are open to test your own strategies. You can spend time and money conducting research advancements like Iron Working, Engineering and Combustion to enhance your civilization's technology. You can build a strong millitary to defend your civilization and use them when necessary to attack other civilizations.
You can expand your civilization by creating many citys and encouraging population growth by using settler units. These settler units can found new cities, explore the surrounding area and create roads, irrigation lines, mines and even railroad tracks between your cities. Roads allow units to travel further during their turn and also enhance trade between cities. Trade and commerce are especially important if you want to maintain your military and cities. You can also build Wonders of the World to give your Civilization the historic appeal and to keep your civilians happy.
This is arguably the turn based strategy game that defined the genre, and for me, it's brilliance is in the simplicity of the game concept and that each game can be different depending upon how each individual player proceeds. More information about the entire Civilization series can be found at civfanatics.com