What does “Master” and “Slave” mean in trigger settings?

In the strategy settings there is Triggers Master/Slave tab, which parameters are divided into two parts: the upper part (from TriggerKeyBuy parameter to TriggerAllMarkets parameter) is intended for master strategy setting, and the lower part (from TriggerByKey parameter to CancelByTriggerBL parameter) is for slave strategy setting, which waits for the trigger key from Master strategy and is not started without it.