The Global Maritime Distress and Safety System (GMDSS) was developed by the International Maritime Organization (IMO).
GMDSS is an internationally recognized distress and radio communication safety system.
The system uses satellites and digital selective calling technology to provide an automatic means of receiving and transmitting distress alerts.
The GMDSS system is primarily a vessel-to-shore alerting system.
The Rescue Coordination Centers (RCCs) receive distress alerts from ships and then coordinate the rescue.
The system also provides a vessel-to-vessel distress-alerting feature.
Other types of messages that could be transmitted by the system are: urgency, safety and routine communications and safety information broadcasts, e.g. (navigation warnings, weather forecasts and rescue messages).