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 a 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 currency item can be seen.

An ore block can be seen in the background which appears to be either a different form of ore or a new texture for the Redstone Ore. Some assume that this ore is a source of the currency item.

With the implementation of the trading system, most or all resources become "renewable" since nonrenewable resources can be traded from Villagers.

Bugs
In 12w21a 1.3 pre-release: Multi Emerald Trading with villagers has a bug Bug1

Bug2