OM/AUM is a root of all mantras.
OM/AUM is a typical combination of words which affects the surrounding and human beings through the vibrations.
Om/aum should to be chanted for enormous number of times to get the results. The results are miraculous.
AUM is composed of 3 elements, 'a', 'u' and 'm'. The fusion of these 3 elements is AUM or OM.