There have been a few major changes to the Age of Empires formula in AOEIII, when you compare it to AOEII, or even Age of Mythology. This section will go over a few of these.
Another major change to the gameplay aspect of Age of Empires III is the fact that your settlers no longer have to return the resources that they collect to a dropsite. In previous games, whenever you sent them out to collect wood, gold, or food, they'd have to return the material to a dropsite (usually your Town Center) before it would be added to your stores. Now, though, you can have a settler halfway across the map from any of your structures, if you wish, because settlers will automatically add what they collect to your stores as they collect it, without needing to drop it off anywhere. This is certainly a welcome change for all but the most hardcore of players, as it'll make your resource collection more efficient and easier to manage, especially when you need to send your villagers away from your base to collect a resource. You can just select them, right click on the resource, and, assuming your opponent doesn't kill them, that's all you need to worry about.
Another new addition, representing the factor of trade in building a civilization, is the Trading Post. Trading Posts can be built at Native American villages on most maps, and will allow you to build and upgrade Native American warriors to add into your army, giving you a more diverse group of warriors to send against your foe.
A more important use of Trading Posts, however, comes when you place them along a trade route. Trade routes aren't on every map in AOEIII, but when they do appear, your Trading Posts will let you receive what amounts to a tax on all the shipments that travel through it. What's more, you can select what specific kind of resource you want to receive, so if you need more wood, or gold, or food, you can get periodic shipments to your Trading Post of that specific resource. You can also upgrade your trade routes to use speedier forms of travel, allowing you to gain your resources more quickly than you normally would.
The Home City
In Age of Empires III, you're going to be representing your chosen civilization in the New World. Since all of the European powers have such a large interest in exploiting the resources of the Americas, they're going to support you as best they can, and this concept is represented in the game with the Home City. With the Home City mechanic, you'll be able to get a number of free units, buildings, and supplies throughout the game. You can check our chapter on Home Cities for more information on this intriguing new mechanic.