https://www.vice.com/en_us/article/akvqgk/why-we-use-lol-so-much

In the 1980s in Canada, Wayne Pearson laughed at a joke his friend typed into an pre-Internet digital chat room called Viewline. “It had me bursting out laughing almost to the embarrassment of doing so in a house by myself sitting at a computer,” Pearson told the Calgary Herald in 2015.

Instead of writing “hahaha,” as he had done before when he found something funny, Pearson unknowingly made history by typing “LOL,” becoming—apparently—the very person to do so.