Trading



The trading system is a gameplay mechanic that allows Players to trade with NPC Villagers.

History
Before the Adventure Update, Notch once answered some questions about an idea he had, NPC Villages, where he revealed some thoughts about them:
 * If you treat the Villagers well (giving them items), they'll give you items back.
 * If you treat the Villagers badly (attacking/killing them), they'll try to do the same to you (feature added with Iron Golems).
 * Raiding chests will anger the owners of the town/chest and they will attack.

On May 21, 2012, Jeb released an screenshot of himself testing the Trading System. The image shows a GUI with buying and selling areas. The bottom area allows the player to sell various items for currency, whereas the top area uses this currency to purchase items. A possible way to buy them would be to put these currencies in the left slot, where the chicken is, and you can scroll through items for the right slot to take the item you choose once you click on it. The player may use the arrow buttons to scroll through a Villager's inventory and select the desired item. Jeb also mentioned that this may be an end to non-renewable resources, supposedly as most can be bought for some price from NPCs. In the image, a red Coin can be seen.

An ore block can be seen in the background which appears to be a different form of ore. Some assume that this ore is a source of the currency item.

Another image released earlier by Jeb shows separated villagers. This tweet also says "this is how I experiment with villagers". With spawn eggs giving random villagers, one would think that by keeping them separate he's going to each profession of villager, perhaps because they each trade different items or are going to. If you look closely at the two pictures, you would see Jeb is trading with the butcher. Jeb is selling raw chicken, and could buy leather armor. Leather armor comes from cows, so there is a good chance trading with different villagers results in different items.