Difference between "IK OANKAR" & "OM"

OM stands for okaar,aakaar,makaar which is
okaar is used for brahma ji who gives life
aakaar is used for vishnu ji who make us lead life
makaar is used for shiv ji who takes life

but the first sikh guru GURU NANAK DEV SAHIB JI said "IK OANKAR"
so the pandits objected that it shud be "OM" n not "IK OANKAR"
then GURU NANAK DEV JI asked them the meaning of "OM"
they said the defination written above
then GURU NANAK DEV JI said "IK" stands for the "ALMIGHTY GOD"
"OANKAR" in this "OAN" is the same as "OM" and
"KAR" is for they all take powers from the "ALMIGHTY GOD"
because they all are puppets of the "ALMIGHTY GOD"
and they do whatever he wants them to do

its written in JAPJI SAHIB
"EKA MAAYI JUGAT VEYAYI TIN CHELE PARVAAN,
IK SANSAARI, IK BHANDARI, IK LAAYE DEBAAN.
JIV TIS BHAVE TIVE CHALAVE JIV HOVE FURMAAN,
OH VEKHE OHNA NADAR NAA AAVE BAHUTA EH VIDAAN.
AADES TISE AADES, AAD AANEEL ANAD ANAHAD JUG JUG EKO VES"

WAHEGURU JI KA KHALSA WAHEGURU JI KI FATEH!!!