Wooden Planks are the easiest non-natural block to obtain during the beginning of a Minecraft world. They function as both a material for structures, as well as a crafting ingredient.
Wooden planks can be created by putting a block or more of wood in the crafting grid (either a crafting table, or the player's inventory grid). When this is done, four wood planks are recovered per piece of wood. It appears as a series of interconnected planks. It is good for creating a support style for buildings and also making houses, huts or shacks.
Wood planks are a renewable resource. Despite being easily burnt down, wood is easy to obtain in biomes where trees can be found and thus useful as a building material. Naturally generated wood planks can be found in Abandoned Mine Shafts, Villages and Swamp Huts. Oak wood planks are used in Villages and Mineshafts, and spruce planks are seen on houses in swamp huts.
As of 1.3.1, Wood Planks are a content of Bonus Chests, for a quicker start in survival mode.
Wooden Plank Types
Oak Wood Planks
Birch Wood Planks
Jungle Wood Planks
Spruce Wood Planks
Dark Oak Wood Planks
Acacia Wood Planks
Wood planks have a wide variety of uses. They are good for giving buildings and homes a cabin-like appearance. However, wood is sometimes discouraged for use as a building material (especially in multiplayer), as your house could be burnt down. Wood planks are an essential crafting material for the most basic of tools and a vital material to those beginning the game and attempting to survive their first couple of days. Wood Planks can be used as Fuel for furnaces (providing 1 1/3 blocks of smelting). If used for smelting, it is more efficient to use wooden planks rather than logs, because they have the same smelting duration and the log contains enough wood for 4 planks. It is not advised to have a fireplace unless you can be assured that your wooden house will not burn down. Try putting non-flammable blocks around your fire area.