The Instagram Notes Numbers Trend, featuring specific alphanumeric codes like o22, o45, and o33, took social media by storm in early 2023 as a new way for users to share their feelings privately in public. Each code corresponds to a specific letter of the alphabet—for instance, o22 represents 'A' and o45 represents 'J'—allowing users to post the first initial of their crush in their status bubble. While it started as a genuine way for Gen Z to signal romantic interests, it quickly evolved into a meme format where people post fake codes, nonsensical strings, or 'o99' to confuse their friends. The trend serves as a modern, digital version of the secret codes used on MSN Messenger or early Facebook, blending nostalgia with the unique UI of Instagram's Note feature.