Moksha is merging with the brahmm the universal consciousness whereas kaivalya is ultimate realisation means when one has complete awareness of his existence and has realised that he is part of that infinite consciousness..

"Aum" and "Om" are just transliterations to English of the original word in Sanskrit, which has its own alphabet - so neither spelling is either correct or incorrect, many older books use "om".

+kumari de silva The point is Sanskrit is a language where the pronunciation matters. You cannot pronounce that word in any other way and expect the effect it is capable of producing. For that we need to assign it a corresponding word in English so that majority can get it. The word is pronounced AUM - अ ऊ म you cannot change this pronunciation. Hence, its better referred as AUM than OM because the latter is closer to its correct pronunciation. And yes, I know there is a letter in the alphabet for this very special word.

+kumari de silva former***

OM IS A VEDIC OR UPANISHADIC SOUND (SABDHAM) VEDHAM AND UPANISHAD- ARE LEARNED SITTING NEAR A TEACHER (GURU) NOT FROM A BOOK BY READING -- UPA + NI + SHAD= UPANISHAD UPA=NEAR--NI= TEACHER (GURU) --SHAD = SITTING & LEARNING --ORAL TRADITION => ZRUTHI --USING ZROTHRAM AND ANNA / PRAANA VAAHA ZROTHAS --HENCE ZRUTHI 'SABDHA BRAHMANN / NAATHA BRAHMANN NEITHER TRANSLITERATION TO ENGLISH NOR WHETHER IT IS A SANSKRIT ALPHABET --THEY ARE IRRELEVANT --HOW A GURU (TEACHER) TEACHES ? --GURU (TEACHER) TEACHES => OOOOOOOO-OOOOOOOO-OOOOOOOM 8 + 8 +7 + 1 =24 "CHATUR VIMSATHI AKSHARA TRIPADHAA SAT KUKSHI HI" "OM ITHI EKA AKSHARAM BRAHMANN" --ONE LETTER PRONOUNCED 3 X 8 TIMES 24 LETTERS IN 3 LEGS OF 8 LETTERS EACH (GAAYATRAM CHANDAS) "SAAMAANI GAAYANTHI" ALSO --THAT ONE SHOULD LEARN FROM A "SAAMAN" EXPERT WITHOUT KNOWING ALL THESE -PEOPLE HAVE MUTILATED--MAIMED--MURDERED -and INCINERATED AT 3000 CELSIUS => "YOGA"

SATHI=100--VIMSATHI 100 /5=20 --+ CHATUR =4 -- HENCE =>20 =4= 24