**maiN to left se maang nikalataa huN [maang = parting] this si so because we are mostly right handed people [some of us who tried to be left handed naturallly, they were spanked on theire hands to stop doing that] so its easier to comb your hair when u part from the left. just go infront of the mirror and try to part from the right with ur right hand...u'll find it difficult if not impossible.