Even though these have been existent for many centuries, nautical flags basically work the same way. The primary use of the flags is to make sure that the ship as well as its crew is constantly safe. Messages can be transmitted effectively to other boats as well as other people inland.
The ICS flag system has been traditionally used by boaters and crews from various parts of the world are expected to have some knowledge on how to send messages to others via the system. NATO ships are also very familiar with the ICS flags although there are other water vessels that might already have adopted newer methods. In most cases, the ICS flags are used by the military with some exceptions among general applications. If you watch regatta events and other related activities, other flag systems are used to send messages. As mentioned before, the ICS flag system has the primary purpose of allowing effective communication between boats and others inland.
As a whole, you will discover that flags belong to four main classes. The single flag will show a number, letter or single message. These can also show whether several flags of the same kind are being displayed simultaneously. Flags can also be used singly such as letter flags forming a word. Some ships use two or more mixes of a nautical flag to make messages as indicated in the International Code of Signals. In 1969, the final official edition was published. The latest revisions on the code were made and presented in 2003.