Often in a day I'll pick up a random bit of trivia that I find really cool, or I'll learn something at school that I find fascinating, or I just have something random that I want to say. I'm pretty sure there are some of you who feel the same, so let's have a thread for this!

This thread is for telling somthing new that you learned today. It can be factual (i.e. "Today I learned why the sky is blue." or "Today I learned that Semitic languages have non-concatenative morphology."), it can be a life lesson (i.e. "Today I learned that eating two-week-old leftovers is a really bad idea." or "Today I learned that scissors should not be used as projectiles.") or it can be a new skill that you've learned (i.e. "Today I learned Kage Bunshin no Jutsu." or "Today I learned how to kill someone with a knitting needle.").

It doesn't matter if it's something everyone else already knows, or even if anyone else even understands what you're talking about. As long as it's something that's new to you, that you learned today. Make your post as long or as short as you want. Include illustrative anecdotes, detailed explanations, or just leave a single sentence.
Let's hear what you learn today!