# Signal Flag Alphabet

Type: Clipping
Date: 2026-06-02
Tags: Letterpress, Maritime, Signal flags, Primary colours, Alphabet
Hero image: /content-assets/clippings/clipping_images/signal-flag-alphabet.jpg
Hero image alt: A letterpress print of the maritime signal flag alphabet, each letter A to Z paired with its flag in red, blue, yellow, and black on cream.
Canonical: https://www.aaronroot.net/clippings/signal-flag-alphabet

International maritime signal flags assign one flag to each letter, plus numerals and pennants. They are used two ways: spelled out letter by letter, or as single flags and short hoists with fixed meanings under the International Code of Signals — "A" (Alpha) for "diver down, keep clear", "O" (Oscar) for "man overboard". They let vessels without a shared language exchange set messages at distance.