What authoritative means
In a multiplayer game the authoritative server is the single source of truth for game state. Clients send inputs like move forward or fire, and the server decides the outcome. Clients never tell the server what their health is or where another player stands.
Why not trust clients
- A trusted client can be modified to cheat: teleport, shoot through walls, or grant infinite ammo.
- Two clients can disagree about who shot first, and someone has to break the tie.
- The server resolves both problems by simulating the world itself and broadcasting results.
The tradeoff
Authority adds latency: a player presses a key, the input travels to the server, the server simulates, and the result travels back. Games hide this delay with prediction and interpolation, covered in later lessons. The server pays more CPU because it simulates every player, but it gains trust and consistency.
Key idea
Clients send inputs and the authoritative server owns the truth, trading extra latency for cheat resistance and consistency.