Minecraft/NPC Villages

Villages are structures in Minecraft that contain several houses, paths, farms, Villagers, and sometimes Iron Golems. Some houses contain chests and/or job blocks, and the crops can be taken from farms.

Finding Villages
Villages naturally spawn in plains, deserts, savannahs, tagia forests, and snowy plains. The style of the village (and the resident villagers) is dependent on the biome. Villages always spawn in the same place on the same seed.

Villager jobs
Villagers can have various jobs based on the available job blocks: In addition, Nitwit villagers (who usually wear green) cannot get a job or trade at all. Trading with a villager will lock in their job permanently, but villagers who have not traded will change jobs if their job block is broken.
 * Blast furnace -> Armorer
 * Smoker -> Butcher
 * Cartography table -> Cartographer
 * Brewing Stand -> Cleric
 * Composter -> Farmer
 * Barrel -> Fisher
 * Fletching Table -> Fletcher
 * Cauldron -> Leatherworker
 * Stonecutter -> Stonemason
 * Loom -> Sheperd
 * Smithing Table -> Toolsmith
 * Grindstone -> Weaponsmith

Trading
Villagers can be traded with, although villagers with no job, villagers with the nitwit job, and baby villagers cannot be traded with. Emeralds are always used in trades. Villagers can sell out of a trade, but if they go to their job-specific workstation afterwards, they can continue doing the trade, albeit temporarily requiring more from the player. Villagers require less from the player to trade if they have the Hero of the Village status effect (can only be gained by starting and clearing a raid) or by curing them from being a zombie (zombie villagers can be cured by hitting them with a splash weakness potion and then feeding them a golden apple, made by surrounding an apple with gold ingots on a crafting table). Villagers have the same types of trades based on job, but the trades themselves can vary. (For example, one villager could sell an enchanted weapon with sharpness and another could sell the same weapon, but with unbreaking instead.)

The Iron Golem
Villages that are large enough have an Iron Golem that naturally spawns and defends the village. The mechanics of this can be abused to make an infinite iron farm.

Zombie Attacks
Occasionally, an event will occur called a "Zombie Horde" during which an abnormal amount of Zombies attack an NPC village. This requires a player to be nearby.