Technology

§ Judged strictly upon his physical capabilities, man is not a particularly well-designed animal. Other animals are faster and stronger, others have keener senses, and others are far better equipped for combat. None, however, is as good as man at "technology" - the ability to create practical applications based upon knowledge of his environment.
§ Take the wheel, for example. Many creatures - mountain goats, for instance - are probably well aware that round rocks move more easily than do flat ones. But beyond figuring out that leaping onto round rocks is a good way to break their neck, goats have not otherwise exploited that knowledge. Man, on the other hand, figured out a way to use that knowledge to his great advantage: he created the technology of the wheel.
§ There are over 80 technologies available in Civilization IV, each representing an important advance in mankind's ability to manipulate the environment.
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Acquiring Technology

§ Each civilization begins the game with knowledge of several primitive technologies. This list varies from civilization to civilization: one may know The Wheel and Agriculture, while another may know Mysticism and Fishing. Beyond the known technologies, there are a number of ways to acquire new ones:
§ Friendly Villages
§ As your units Explore the world, they may encounter tribal villages. These villages may attack your explorers, or they may give them maps, money, or new technology. You need to find them quickly, however; there are only a limited number of tribal villages on the map, and all civilizations want them.
§ Diplomacy
§ As the game progresses, you will be able to acquire technologies from other civilizations through trade. See Diplomacy for details.
§ Research
§ You can discover new technologies on your own, through Research. This is the most common way to acquire technologies. See that section for details.
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Choosing Techs to Research

§ When you have completed research and learned a new technology, the "choose a technology" menu appears and you must choose another technology to begin researching. At that time the game will provide a list of available technologies for you to choose from. Many techs have "prerequisite technologies" that you must know before you can learn the new technology - for instance, you need to know the Animal Husbandry tech before you can study Horseback Riding and get the versatile Horse Archer units.
§ Some technologies may have multiple prerequisites to begin researching them; other technologies require one tech OR another tech to research. Monotheism is an example of the first group; it requires Polytheism AND Masonry. Animal Husbandry is an example of the second group; it requires Hunting OR Agriculture, but not both. A tech will appear on your list only when you have learned the necessary prerequisite technologies.
§ The Tech Tree: The extremely useful Technology Tree (F6) displays all of the technologies in the game and how they are interrelated. You can select which tech to research from the tree, or choose a research path by clicking on a tech that you want which is not currently available to be researched. The game will choose the shortest possible path to reach the tech you have selected.
§ Time to Research: Each technology requires a certain number of "research points" to learn. The "choose a technology" screen lists the number of turns it will take to learn each technology - at your CURRENT research rate. See Research to learn how to increase your research rate and thus shorten the time it takes to learn new technologies.
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Changing Research

§ You are free to change what your civilization is researching at any point in time. You can do this by clicking on the research bar at the top of the main game screen, or by opening up the Tech Tree (see above) and selecting a different tech there. Unlike previous Civilization games, there is no penalty for changing research paths. You can research half of one technology, change to a second technology and finish it, then return to the first one and pick up right where you left off before.
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Effects of Technology

§ Technologies allow you to do cool stuff: build new units, wonders and buildings, change your civics, discover a new religion, trade different stuff with other civilizations, and so forth. Some techs give special bonuses to the civilization that first discovers them. Note that some techs render some Wonders obsolete.
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