Lichess

Lichess is free and open-source Internet chess server. The chess server is run by a non-profit organization, which is also called Lichess. The Lichess chess server was created in 2010. 
In April 2021, the United States Chess Federation reviewed how Lichess deals with cheating in online chess. After this review, it endorsed Lichess as a secure place to play chess for its members.
Titled Arenas.
Lichess runs tournaments called Titled Arenas, in which only players who have a title are able to play. As of February 2021, World Chess Champion Magnus Carlsen has the most Titled Arena wins, with 15.