flaggsignaler

Flaggsignaler are systems that convey information over a distance using flags. They have a long history in maritime contexts, where ships use hoisted signal flags and, less often, hand-held flags to communicate. The term covers both flags raised on masts and flags waved from decks or shore platforms. Flag signaling relies on visual sightlines and is typically independent of voice or radio channels.

The most widely used modern framework is the International Code of Signals (ICS). It assigns meanings to individual flags and allows messages to be formed by combining flags or by using numeral pennants. Flags can spell out letters or convey pre-arranged signals for safety, navigation, or distress. In addition to hoisted flags, semaphore uses two handheld flags in fixed positions to spell the alphabet, enabling signaling without a flagpole. Semaphore was common before radiocommunication and remains a standard demonstration skill and training exercise.

Historically, flag signaling enabled fleet coordination at sea and allowed distant ships to exchange information when other channels were unavailable. With the rise of radio and satellite communications, practical reliance on flag signaling diminished, but the practice persists in training, ceremonial contexts, and as a backup signaling method. Coast guards, naval forces, and merchant ships may still use flag signals in certain operations, and signal flags are widely displayed during events and parades.

See also: maritime signal flags, semaphore, International Code of Signals.