Just found out about it a minute ago!
"ELO" is called Elo because a professor "Arpad Elo" named it that in the mid 1900s, and its used in Chess and other zero-sum games. It's a system of making the match as fair as possible.
(I just thought it stood for something like Electronic League Oscillator or something)
_**Welcome to Off-topic!**_
There are a lot of other boards. Are you sure your post doesn't go in one of them? It’s definitely possible. We just want to double-check. Well, anyway... if you're SURE it can't fit anywhere else, Off-topic is probably the board for you.
Follow the **[Universal Rules](http://boards.euw.leagueoflegends.com/en/c/announcements-en/3eWpXbJi)** and keep content focused on appropriate topics for these Boards.
Use the report button for any post you think deserves the attention of our moderators.