The ratings make it possible to compare the playing strength of chess players, so you find players of about your level. A new member starts with a rating of 1800 and after a rated game that number changes. The change depends on the result of the game and your opponent's strength.
On our website we distinguish beween bullet chess (less then 3 minutes), blitz chess (from 3 to 10 minutes) and classical chess (more than 10 minutes).
Note that the ratings shown are only affected by the games played on chess24. There can be significant differences to FIDE Elo or national ratings.