Three calls of pan-pan are used in radiotelephone communications to signify that there is an urgency on board a boat, ship, aircraft, or other vehicle but that, for the time being at least, there is no immediate danger to anyone's life or to the vessel itself. This is referred to as a state of urgency. This is distinct from a mayday call, which means that there is imminent danger to life or to the continued viability of the vessel itself. Thus "pan-pan" informs potential rescuers (including emergency services and other craft in the area) that a safety problem exists whereas "mayday" will call upon them to drop all other activities and immediately initiate a rescue attempt.