The games are run on servers, which keep track of every player’s position, health, rotation, etc. and relay the relevant information to the players.
This means that, as a player, your system only needs to know your position, health, rotation, etc. and only has to handle the information for other players if they’re within a certain distance from you. Basically, on your system, only things within a 50 m radius of your position need to be handled and everything else is handled by the server.
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