The caps lock key is a vestige of mechanical typewriters, mimicking the function of the "shift bar," which literally shifts the typewriter in order to type capital letters. Today, the key resides on the left side of most keyboards, and while similar commands like bold and italics are relegated to keyboard commands, the caps lock keeps its coveted spot beside the home row (except for in Chromebooks, which recently replaced the key with an "everything button".) Some Reddit users aren't big fans of all-caps and have remapped the caps lock key to other keys like backspace, escape, or enter.
But other internet users are major caps lock fans.
In 2000, Derek Arnold declared October 22 International Caps Lock Day, suggesting that for the entire day, everyone types on caps lock. The software developer explained the holiday on a now-defunct webpage:
International Caps Lock Day is in fact a testament to the small mindedness of certain Western individuals: the majority of the world's population writes in scripts which have no concept of letter casing. Therefore it is advised to laugh at anyone who invokes this day as an excuse to dismiss local typographical conventions: they are simply making an ass out of themselves.Today
After the death of Billy Mays, the impassioned infomercial star prone to yell-talking ("BUT I'M NOT DONE YET!"), Arnold declared a second caps lock day to take place on June 28th, the anniversary of Mays' death.