Horns are used on ships as in all motor vehicles. Horns, which are often used in case of danger, also indicate that ships are moving. Theoretically used horns are three parts. Compressed air horns are the first part, also called bellows horns. The horns in the second group are the horns controlled by a mechanical switch. The third group of horns are the horns that operate according to the magnetic field principle.

Today, motor vehicles prefer the third group of horns. Ships use bellows horns. Bellows horns, also known as air horns, are horns with a loudness higher than others. They can transmit their voices to very remote points in one press. It is therefore suitable for ships.