There are varied interpretations to why the horseshoe is considered a symbol of good luck. Since the horseshoe protects the horse’s fragile hoofs, they are considered to protect everything they touch. The horseshoe also picks up its lucky reputation because it is considered to be made from iron, a metal believed to repel evil energies.
The way the horseshoe is hung varies according to individual beliefs. Some feel that the horseshoe facing upward holds the luck and power for the people and the place it is in, while the other theory claims that when facing downwards the horseshoe brings good luck and power to all that walk below or beside it. You can hang one in each position if you are doubly superstitious.