Le mot sacré

My father came back from India 3 weeks ago and brought some things for me and he offered me a wondeful silver coin!! And on it, there's Ganesh on one face and on the other, le sanskrit word: Om (or Aum).

But what's "om"?
Om is a sankrit sacred syllabe, it is said that this is the original sound and that with this syllabe we can pronounce all the other words.
This syllabe was created before the universe and created the Gods.

When we write AUM:

• A symbolizes the arousal
• U, the dream
• M, the sleep

Om, is a kind of equivalent of "Amen"
In the Hindi universal prayer, the first word is Om:

There are a lot of things to say about this syllabe of course...

Source: wikipedia (English version)