Recognition signals
- human and technical communications
- concept of information
- signal
— discrete part of a communication
— unidirectional and bi-directional

Distress signal

Smoke signal

Telegraphic signal

Telecommunication signalling

Code of Signals

Maritime signal flags
Maritime flag signalling

Military signals

- military communications
- Naval flag signalling


Traffic light
Railway signal

Unless otherwise stated, the content of this page is licensed under Creative Commons Attribution-ShareAlike 3.0 License