In 1901 the flag alphabet was first introduced in general with the edition of the International Signal Book. The flag alphabet published by the Board of Trade in 1857 served as the basis. Since its inception, it has been revised and streamlined over the years.
Pennants and Stander
The basic principle of the flag alphabet has not changed since 1901. However, the number of stander and pennants has increased over time. In addition to ten number and 26 letter pennants, there is a signal pennant, four auxiliary posts and two track and one target pennants for regattas. In general, a maximum of four different letters are set at the same time, which are read from top to bottom.

Signals from the International Signal Book are given as one, two or three letter signals. With signals of more than three flags z. B. bearing, date, time, positions indicated. As already mentioned, only flag signals from up to four different flags at the same time are common. The use of the international signal book is always announced to the counterpart by the answer flag (AP) or by radio with the word INTERCO.