One is to win at all costs. This player typically plays on Deity and has a militaristic-expansionist strategy.
The other type typically plays on King or Emperor and is interested in diplomacy and winning with a decent reputation intact.
This is not to imply that diplomacy-type players are a bunch of saints. I usually play a somewhat defensive tech game where I try to get a spaceship win. This involves, typically, 8-12 cities, careful diplomacy and a lot of emphasis on trade and city management. I wouldn't call it isolationist, because I like to explore, trade and make alliances. And I'm perfectly willing to do limited warfare. I'm just not looking to own the map, or even necessarily a full continent. I definitely enjoy hoovering up weak Civs nobody cares about and encouraging the stronger Civs to war with each other while I pick out all of the good city sites!
My fundamental strategy rotates around being the second-best Civ on the planet and playing catch-up in the space race. The disadvantage of this strategy is that there is a definite chance you could lose the game, even right up to the last few years. There are a lot of plusses, though. You don't have to worry about being ganged up on. You can play the AI's off each other using diplomacy (psst, buddy, declare war on them!) The endgame can be *very* tense and exciting, with nukes falling everywhere just as your spaceship is about to land. You can feed on weak AI's without fear of world censure. Also, knowing there is a stronger Civ out there lends a certain 'rebel' feel to the game, especially if you kick their butt. Finally, world peace scenarios are possible during all stages.
A policy of conducting small, limited wars with nearly every Civ you meet actually encourages global peace. AI's that are fighting you have an incentive to declare peace with other AI's so they can focus on their war with you. Try to make peace immediately with the Civ that looks likely to be #1 in the game, so you don't get bogged down in prolonged warfare in the mid-game.
The best results seem to come when playing Aztecs, Spanish or Persians. Choice of civ may influence seeding of the goodie huts.
This doesn't always work, but even when it fails there isn't much time invested.
Naval Dominance:
Alphabet, Map Making, Seafaring, Masonry, Mathematics, Ceremonial Burial, Mysticism, Astronomy, Navigation, Writing, Code of Laws, Literacy, Physics, Iron Working, Magnetism
Always be on the lookout for chances to jump way ahead on the tree via trade or conquest. For instance, if you grab Astronomy early, you can skip Masonry through Mysticism in my Naval Dominance tree.
Try a tech tree that gets you the marketplace and bank early.
Note that a tech strategy is fundamentally a trade strategy, since science output comes from trade.
Produce all your defensive units from a single city with an up-to-date barracks and good production capacity. (courtesy of iadkins@ozemail.com.au)
Build a single 'tech city' with Colossus, Copernicus' Observatory and Isaac Newton's College. If you build it on a riverbed area it's even better. You don't even have to build a road to get a trade icon on the rivers and when you get bridge building you can add a road for two icons! It is possible to generate upwards of 250 beakers in a single city.
Reassign caravans to your top trade city and send a lot of them across the seas.
Controlling the location of the theatre of war is one of the great, but often over-looked, strategic elements in the game.
Do some limited beachhead based expansion on other continents to establish a relationship with other Civs and scout for the prime city locations (Explorers are great for the scouting role - use Partisans later on).
Beachheads give you diplomatic representation on other continents, without the overhead of conducting full-scale war. Do plenty of exploring. You can have a moderately large empire by pushing ships around the map and taking prime undeveloped real estate. Consider doing a few city subversions (x2 to avoid an incident). Do them far away from your capital.
A beachhead warfare policy also encourages the AI's toward peace. They seem more inclined to want to end wars on their home turf (naturally enough) and will often continue to fortify around your 'colony', thereby pulling their resources (and the AI equivalent of their attention) away from other computer players.
The unit which captures a city is immediately repaired, so select a unit that is low to send triumphantly in.
If relations with a strong neighboring Civ seem tense late in the game, flying planes back and forth along the border with them may discourage aggression.
Bombers
A combined Bomber/Paratrooper army is a very flexible city-winning machine. Great for island hopping.
Leaving Bombers over nearby mountaintops and hills before taking a city prevents the AI from placing enemy partisans there.
Spies
The veteran Spies produced by communism can be a tremendous weapon late in the game. Poison can reduce key cities very quickly. Exploit railroad networks to move spies across great distances.
Ally with a warlike Civ and trade your civil advancements for their military ones. They will lag behind you in science development so won't be competing too closely in the space race. Fight one or two small wars of conquest at the very start of the game and look for a Civ on equal footing to be an ally. Then turn to peaceful improvements and wonders.
Your ally may ask you to come to his aid by declaring war on another Civ. Usually you can do this without actually attacking anyone else. It is particularly safe if your ally's enemy doesn't share a border with you. If you find you just can't join the conflict, your ally will ask you to offer a tech instead. Go ahead and do it.
If another Civ gives you trouble, invite your ally to declare war on them (usually your ally will do it without any prompting from you - one of the best features of alliances).
Don't become the most powerful Civ, because the AI's will then attack you no matter how nice you are. Stay in second or third position and sneak a spaceship in at the end. Let your ally have supreme power, if they can achieve it. Focus on tech and cash and support their military might.
Share world maps in mid-game. You'll usually get the best effect from this around 1500 AD or so.
Feel free to ask for gifts, particularly if your ally has a lot more cash than you do. They'll warn you if they're losing patience.
Build the U.N. If you have some cash, play the AI's off against each other. Get them to focus their resources on war while you aim for space. It also helps prevent them from trading advances late in the game.
Towards the end, build some defensive improvements (SDI, SAM, Coastal Fortress) in your main cities. Even your ally may turn against you when they realize your spaceship will arrive before theirs. If they are still allied after you launch, send them to squash your new enemies.
Equip each city with at least 2 spies, to guard against espionage and sabotage.
The diplomatic game is a delicate balance; practice and experience count for a lot. As a reward for your patience, there is incredible potential for satisfaction and narrative intrigue in a diplomatic game.
Build extra caravans early on and stockpile them for building wonders and establishing trade routes.
For a 3 module ship that is fusion powered:
6 components, 15 structurals, 15.7 years to reach AC
8, 17, 13.2
10, 21, 10.0
12, 25, 8.3
14, 29, 6.7
16, 33, 5.7 -- This is the fastest ship you can build.
(courtesy of vtnmswndr@aol.com)
Wait for the top Civ(s) to launch spaceships and then send a faster one that will pass them up on the way to Alpha Centauri. Launching a 3, 16, 33 will reduce the number of rounds that Civs with 'spaceship envy' will be able to annoy you with their attacks.