Every ship in the squadron, for instance, takes the uniform of the day from her.
The number of sick each morning must be reported by signal; all orders (and they are legion) are transmitted by wigwag or bunting; scores of questions are asked daily by each ship, and it is indeed seldom that the signal yards of a flagship are bare of colored flags.
In the American navy the present methods of communication are by the use of flags representing numerals, by the Meyer code of wigwag signals, and by a system of colored electric bulbs suspended in the rigging.

The latter system is called after its inventor, Ardois.
In the daytime, when ships are within easy distance, wigwagging is commonly used.

A small flag attached to a staff is held by the signalman in such a position that it can be seen by the ship addressed.

A code similar to the Morse telegraph alphabet is employed.

By this system the flag, when waved to the right, represents 1, or a dot; and 2, or a dash, when inclined to the left.