The sea has always provided cheap and efficient transport. It has also allowed different wars to be influenced by the naval forces of the factions involved. Goods have been shipped from one place to another with minimal cost and delay. However, it has its share of accidents and dangers. This means that shipbuilders and merchants have to do something about how they will minimize the risk to human lives. They also have to maximize the chances of rescue from their escorts.

People developed the coast guard. This group of elite rescuers is tasked with searching for troubled vessels so that they can rescue the people on board. However, for them to be effective, they have to spot the vessels and the people even in bad weather. This is why vessels and lifejackets have strobe lights on them. Vessels also have nautical flags so that they can be spotted and identified in broad daylight. Sometimes, they also have infrared strobe light so that coast guard helicopters can easily spot them using infrared cameras.

The sea has also been used as a means to convey messages. These days, the LGBT movement has put up pride flags on different naval vessels. This is because they want the world to know that whoever sails on that vessel supports the movement. And since they need all the support that they can get, they would have to use all means possible so that they can get that support. After all, spectators that can see proud supporters could be convinced to join and support the cause.