before they completed their move. For example, if the time control is 90+30 (ninety minutes of main time per player with a thirty-second increment each move), each player gets an additional thirty seconds added to their main time for each move, unless the player's main time ran out first. Under FIDE and US Chess rules, the increment is applied to the first move as well. For example, for 3+2 each player starts with three minutes and two seconds on the first move. Not all digital clocks automatically give the increment for move one and thus for those that don't, the increment time has to be added manually to the main time so each player gets the increment for move one. In online chess, players may make multiple premoves (such as moving a knight back and forth) to give them additional time to think and/or avoid running out of time. Bronstein delay (named after Grandmaster David Bronstein who invented this timing method)—this timing method adds time but unlike increment not always the maximum amount of time is added. If a player expends more than the specified delay, then the entire delay is added to the player's clock but if a player moves faster than the delay, only the exact amount of time expended by the player is added. For example, if the delay is ten seconds and a player uses ten or more seconds for a move, ten seconds is added after they complete their move. If the player uses five seconds for a move, five seconds is added after they complete their move. This ensures that the main time left on the clock can never increase even if a player makes fast moves. As with increment, the delay time is applied to the first move under FIDE and US Chess rules. Simple delay (also known as US delay)—with this timing method, the clock waits for the delay period each move before the player's main time starts countdown down. For example, if the delay is ten seconds, the clock waits for ten seconds each move before the main time starts counting down. Bronstein delay and Simple delay are mathematically equivalent. The advantage of Bronstein delay is that a player can always quickly see exactly how much time they have for their next move without having to mentally add the main and delay time. The advantage of Simple delay is that a