Shhh! Not So Loud!
Somewhere along the internet timeline, typing in ALL-CAPS became known as rude behavior when communicating with someone. It came to symbolize anger and frustration. When you'd fire off a pointed missive to someone with all-caps, you were yelling at them—and weren't being shy about it. This quickly became a basic violation of proper netiquette.
Let's examine how this trend developed. If you have any thoughts on this matter, let's hear them (not in all-caps, though, please?) on Twitter or Facebook (dictionarycom).