The Elo rating system is a method for calculating the relative skill levels of players in competitor-versus-competitor games such as chess. It is named after its creator Arpad Elo, a Hungarian-born American physics professor.
The Elo system was invented as an improved chess rating system and is also used in many other games. It is also used as a rating system for multiplayer competition in a number of video games, and has been adapted to team sports including association football, gridiron football, basketball, Major League Baseball, competitive programming, and esports.
The difference in the ratings...