The file itself carries the marker Created in Messenger Plus, the add-on that let MSN Messenger users send short custom sounds in chats during the 2000s messaging era. Clips like this one were traded as tiny reaction packs, and oh my gawd became a reusable punchline for shock and sarcasm. As those sounds migrated to forums, video editors and soundboards, the exaggerated spelling stuck because it matched the pronunciation. It survives today as a quick meme reaction rather than a quote from a specific show or film.