Elo ratings, invented by the Hungarian statistician Professor Arpad Elö, express the playing strength of chess players. Strong club players may reach 2000 points, International Masters are usually 2300 to 2500, Grandmasters up to 2700, with a very small number of players exceeding event that (Garry Kasparov is the only player in history to exceed 2800). Twice a year the world chess federation issues an Elo rating list with ratings for tens of thousands of players.

 

Here's a list of rating categories