The first recorded use of the abbreviation “OMG”, which stands for “oh my god,” “oh my gosh” or “oh my goodness,” was from a letter written in 1917 by Lord Fisher to Winston Churchill. In the letter, Lord Fisher jokingly refers to a new order of knights signified by the letters “O.M.G. (Oh! My God!).” Many decades later, the abbreviation became a part of textspeak — the common abbreviations used by people who are communicating via text messaging or through social media.
More about common abbreviations:
Contrary to popular belief, the international distress signal SOS does not stand for “save our ship.” It is not an abbreviation for anything.
In textspeak, LOL means “laughing out loud.” Healthcare workers, however, have historically used the abbreviation to mean “little old lady.”
Law enforcement personnel have used the term OMG in reference to “outlaw motorcycle gangs.”