Doors are blocks used for minor or major protection, and are controlled mainly by the Player. They are obtainable through crafting, as seen below, or finding them in NPC Villages and Strongholds. They come in two varieties: wooden doors, which are made from wooden planks and can be opened by hand, and iron doors made from iron ingots which can only be opened by power from a Button or another connected Redstone source. Doors are hinged on a side and have two states: rotated clockwise and rotated counter-clockwise.
Zombies are able to knock down wooden doors on hard and hardcore mode, and will "siege" it, eventually breaking it, in any lower difficulty. Villagers can open wooden doors and enter, but cannot use buttons or levers to open iron doors.