That&#x27;s the traditional term, but it has specific meaning in game network programming. For instance we never send back the &quot;error accumulated&quot; to the server. Instead the server usually sends a PVS(potentially visible set) that the client handles displaying in a meaningful way(and reconciling and discrepancies). This PVS set is usually absolute values but at a discrete snapshot in time(of which the client can never be certain due to latency and there not being a single global clock). The client is basically guessing where the simulation is going and then smoothly handling(normally interpolation over your usual time-slice) differences from the server snapshot.<p>That PVS is why you&#x27;ll see map hacks where people can see through walls and whatnot. The server is doing less expensive checks(not doing a ray cast per-client to client which is n^2) and the cheat takes advantage of that data in memory.