Today, navigation is unthinkable without radio communications. Shortwave radio stations, satellite radio communications, emergency beacons and radar transponder buoys - it is simply necessary for the captain of the yacht to understand all this, and sometimes it is necessary. Understand and use correctly. Reliable radio communication at sea is the key to solving many problems: from security to business and management communications, both between ships and with the shore. This manual introduces the various types of communication equipment, the rules for their correct use, and emergency radio communication procedures. Designed for learners and novice yacht captains.