
The rules of “netiquette” are not exactly static or undisputed. Are emoticons appropriate in formal emails? Are “trigger warnings” thoughtful or over-the-top? Are you irritating everyone you email with your “signature”? The uncertainty that typically surrounds these questions makes it all the more remarkable that there’s one convention that is incontestable: Typing in all caps is internet code for shouting, and it is rude.
People have long used capital letters to set text apart and convey its importance, but upper case letters haven’t always signified loudness. The first bloggers may be responsible for that development: Linguist Ben Zimmer pointed me to old “Usenet newsgroups” – the precursors of the forums and Reddit threads that dominate the Internet today – where people hashed out what capital letters would mean online. In 1984, one user had to explain: “if it’s in caps i’m trying to YELL!” In one of the best clues into the evolution of this convention, another user, Dave Decot, summed up the situation as he understood it in 1984: