Civilizations can no longer trade with technology, as in previous versions of the game, instead civilizations can carry out common technological enterprises. Two civilizations at peace can form a research agreement that requires an initial investment of gold and provides the two civilizations with a certain amount of science as long as they remain at peace.  Before the PC 220.127.116.112 version of the game, civilizations were equipped with unknown technology after a series of twists and turns of uninterrupted peaceful relations. It is possible for a civilization to sign a research agreement just to get an enemy to spend money that could be used for other purposes; AI civilizations are programmed to sometimes use this tactic before declaring war.  British actor W. Morgan Sheppard delivers the story for the opening films of the original game and its expansion packs, quotes on the discovery of new technologies and the construction of tourist sites and the introduction of the player`s chosen civilization at the beginning of each new game.  The money you invest in the contract is lost. That`s not necessarily a bad thing – if you can go to war with someone, they`ll lose the money they could have used to defend themselves. Flat Boosts to Science: Trade RoutesIf you have studied fewer techs than a Civ or influential through tourism, you get science for trade routes, or they will.
In most cases, both Civs receive some science for the trade route, depending on those that are more advanced. Both are the same, it would be a bit of science each. This is most relevant at the beginning of the game, where the link with Civs can determine your own lack of science. Going from 30 to 33 sciences with a trade route is an important leap. The science from a late game of the trade route is negligible, especially because there is no push of % modifiers. Just send multiple routes to Babylon or another advanced Civ to increase your gold per turn and any technology you will explore to shave one or two rounds. This science is added to the city edition after everything else has been calculated. As AI is usually a scientific advance in the early game, finding business partners can greatly help your science editing and help you get the technologies you need to transmit them.
The caravan and port, with several technologies, will increase the supply of land/sea trade routes. What to explore to optimize technologies are always prioritized, like granaries, if they help you more. You`ll also want City Connections to support your revenue, so roads and ports are important, as are trade routes.