The Armor Stand is a block that is purely aesthetic and provides no use outside of displaying armor. It was added in the Bountiful Update, also known as the 1.8 Update. It can also display player heads and mob heads.
The Armor Stand is crafted with one stone slab and six sticks, as shown to the left.
Right-clicking on the stand with a piece of armor will either place it on the stand, or switch it with another piece of the same type that was already present.
They can also be spawned using /summon, which is useful for creating player statues, because of the ability to ad arms, remove the slab, etc.
Redstone and Command Blocks
They have been used in many Redstone creations, including a roulette wheel, a crane, dice, and a lot more. They mostly are used in creations that require scoreboards, as they are entities.